Article 91 – ‘The coffee debate’

Hi and welcome to Taiga Bonzai, in this short post we discuss the arguments surrounding the use of coffee as a fertilizer or mulch in soil mediums.

Introduction – in 1958 coffee was added to the list of foods and beverages recognized by the World Health Organization (WHO) as safe for human health. This ended many years of debates regarding the effects of coffee on human health. Recent studies show that coffee alleviates asthma bouts, allergies and prevents tooth decay it also activates burning of fats in the body, replenishes potassium deficit and contributes to the improvement of the cardiovascular function. Coffee is a powerful source of antioxidants.

The main biologically active component of coffee is organic alkaloid caffeine that is found in various quantities in more than a hundred plants. However, only coffee, cocoa berries, kola nuts contain quite significant amounts of caffeine. Numerous studies suggest that due to its caffeine content coffee increases the speed of human reaction, aids concentration, associative thinking, relieves drowsiness and improves mood. Arguably it all depends the amount of consumption.

Coffee in whatever form ground, roasted or granulated is acidic, but when processed into a beverage the grounds lose their acidity hence they become neutral although there may be a small percentage of acidity remaining. Coffee grounds make good fertilizer because they contain several key nutrients required for plant growth. They also attract worms and decrease the concentrations of heavy metals in the soil. Coffee houses often give spent coffee grounds to horticulturists, because they are a waste product a free available resource.

Nonetheless, there are differences of opinion some horticulturists argue that coffee grounds should not be used as they have a disastrous effects on certain plants for example. Geranium, asparagus fern, Chinese mustard, Italian ryegrass and pin oak. The probable cause for these negative results is due to the amount of coffee grounds used either as a mulch or mixed in the actual soil medium; but the question is how much to use. This Kengai (cascade) Juniper (below) gets a small sprinkle (half a teaspoon) of unprocessed coffee grounds on the top of the soil medium each spring, which slowly releases the acidity when watered.

Spent or waste coffee grounds if making ericaceous soil can be added to the mix, but in small quantities and preferably dried out prior to combining all the ingredients together. It is important to create a correct balance too much of a particular ingredient can do more harm than good. Because it can decrease the availability of plant nutrients including phosphorus and molybdenum, that increases the availability of some elements to toxic levels, particularly aluminium and manganese. Essential plant nutrients can also be leached below the rooting zone.

According to the Oregon State University the acid in coffee beans is water soluble and bad for plants because they are allelopathic, which can reduce the growth of other nearby plants that compete for minerals and water. It is also stated that earthworms can perish when in contact with Caffeine. However, others argue that caffeine in processed coffee ends up in the cup not in the spent grounds that become almost neutral with a pH of 6.5 to 6.8 which is close to the midway point of 7 on the pH scale. (Shown below)

As stated we use coffee grounds both unprocessed and processed on our bonsai and there have not been any problems to date. Nonetheless, there exist many written articles on the subject, which can be found on the world wide web, whether you wish to try spent coffee grounds as a fertilizer or mulch that is your decision.

Since we returned from our break in March (17th) 2021 with article 46 “The road is long with many a winding turn” we have posted 45 articles non-stop however, we are forced to take a break due to the fact that we are moving to a new location. This task is going to a real headache considering what we have accumulated after 20 years in one place. We hope to be up and running again mid spring, until next time, BW, Nik.

Article 90 – ‘Calcium build up removal’

Hi and welcome to Taiga Bonzai, in this post we discuss the problems of alkaline staining or calcium build up and how to remove these marks from glazed and unglazed ceramics. But first it would be prudent to discuss some of the chemicals used in tap water that contribute to the problem.

Introduction – tap water having a pH range from 6.5 to 8.5 (depending on your particular region) contains various chemicals some thought to be beneficial, but scientific tests have shown this conception to be a misnomer. For example, Fluoride (F) thought to assist in the reduction of tooth decay is a neurotoxin an endocrine disruptor, able to damage the thyroid gland, calcify the pineal gland and interfere with bone formation. Many countries have now banned its use due to health risk.

Other toxic chemicals – include Chlorine (CI) a strong disinfectant added to drinking water as a purification technique, it is a reactive chemical that bonds with water, including water in the stomach producing poisonous hydrochloric acid. Mercury (Hg) a naturally occurring element usually a bi -product of mining and industrial practises. Arsenic (As) used in a multitude of industrial processes, Lead (Pb) major toxin that still exists due to corroded piping systems that is extremely toxic.

PCBs (polychlorinated biphenyls) are chemicals used for industrial purposes such as insulation, machinery, oil, paints, adhesives, electronics and fluorescent lights. Perchlorate (CI04) HCB or Pentachlorophenol (C6) and DDT (C14H9Cl5) (Dichloride-Phenyl-Trichloroethane) all have detrimental effects. As do modern insecticides and herbicides including Glyphosate which, are highly toxic, to read the full post on this topic see ‘article 36 – a teaspoon of vinegar’ part 2.

Acidic cleaning – acid cleaning agents are used to remove scaling and other inorganic deposits. Normally, the active ingredients in such solutions include chelants and mineral acids along with corrosion inhibitors and surfactants. Acid cleaning is a useful method to clean materials and wash away corroded parts, the most commonly used cleaning agents include hydrochloric acid, also referred to muriatic acid. Other substances include sulphuric, vinegar (acetic) and citric acids, for hard surfaces, which can assist in removing build-up of calcium deposits.

In brief the potency of the above mentioned acids, Hydrochloric acid H⁺Cl⁻or H₃O⁺Cl⁻ is an aqueous solution of hydrogen chloride, a solution with a distinctive pungent smell of ‘stale almonds’ and classified as a strong acid. It is a component of the gastric acid in the digestive systems of most animal species, including humans; but is still highly toxic due to its concentration.

Sulphuric acid known in antiquity as oil of vitriol is a mineral acid composed of elements that include sulphur, oxygen and hydrogen, with the molecular formula H₂SO₄. It is a colourless odourless viscous liquid that is miscible with water. Hydrochloric and Sulphuric are arguably the most potent chemical agents used in acidic cleaning of alkaline contamination especially on pipes and drains. If used undiluted will have instant effects, hence protective clothing should be used at all times.

Acetic acid, systematically named ethanoic acid is an acidic, colourless liquid and organic compound with the chemical formula CH₃COOH. Vinegar is no less than 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water and other trace elements. Vinegar is extremely effective when added to tap water which if left to stand for two days softens the hardness of tap water. (see article 35 ‘A teaspoon of vinegar’)

Citric acid an organic compound with the chemical formula HOC(CH₂CO₂H)₂ is a colourless weak organic acid occurring naturally in citrus fruits. In biochemistry, it is intermediate in the citric acid cycle, which occurs in the metabolism of all aerobic organisms. Although these two acids (vinegar & citrus) have the ability to clean alkaline contaminated items, they lack the potency to remove all traces moreover, using such in large quantities would not be cost effective.

Recommendations – hydrochloric acid H⁺ Cl⁻ or H₃O⁺ Cl⁻ and sulphuric acid H₂SO₄ can be purchased at most hardware or large supermarket chains however, obtaining the latter might pose some difficulty hence an explanation as to why it is needed due to its history of misuse. According to Patrick Knox in his article in the UK SUN newspaper 14:17, 24 May 2018 Updated: 14:18, 24 May 2018 he states that “in the UK (H₂SO₄) has been used by psychopathic sadists to inflict agony and disfigurement on their victims” thus a license to purchase is now required.

Research – after some enquiries as to what is available, we found that here in Scandinavia hydrochloric acid can be found almost anywhere and can be purchased quite easily as permits are not required, hence the following product was obtained a – 4 litre container for €24,95. After a few experiments to find the correct combination of the acid solution and water, a few tests on chrome taps and other faucets were cleaned with all alkalinity and calcium build up removed.

The next step was to experiment on bonsai ceramics to test our theory, image 1. depicts a bonsai pot drip tray with a large heavy alkaline calcium build up over a two year period. To attempt to remove this unsightly mess via the use of metal instruments would be unsuccessful moreover, the risk of damage to the glaze would be inevitable. A solution using 50% hydrochloric acid and 50% water was made and the tray was submerged for 30 min.

Alkaline and calcium corrosion

After the alloted soaking time (30 min) the tray was inspected and all traces of alkaline calcium build up were removed, the solution itself was all that was required. Hence the need for brushes or scouring pads including wire wool were not required, the tray was then rinsed with clean water to remove any traces of the solution then dried. Image 2. shows the result of the cleaning process.

Alkaline and calcium removal

Power of acidity – in looking at the dirty drip tray one might think that “if alkaline can do this to ceramics, what effect does it have on the human stomach” in short the answer is not much. The human body has various fluids containing different pH values. Food when consumed goes through a process the upper part of the stomach has a pH of 4 to 6.5, while the lower part is highly acidic with a pH of 1.5 to 4.0. It then enters the intestine which is slightly alkaline, with a pH of 7 to 8.5, hence the body’s fluids can easily adapt to changes in alkaline and acid and vice versa.

Different manufacturers – there are various manufacturers that produce acid cleaner the world over and all will have different brand titles depending on what name/s they are assigned. But providing the label states that it is muriatic acid – hydrochloric acid H⁺Cl⁻or H₃O⁺Cl⁻, this is the chemical we prefer to use because of (a) its ability to remove alkaline calcium build up (b) it is relatively safe if used according to the manufacturer’s instructions opposed to the more dangerous sulphuric acids.

Disclaimer notice – as stated there are similarities in hydrochloric acid production in animals and humans via their digestive systems, but manufactured hydrochloric acid is a concentrated toxic poison and should not be used on household appliances regardless of the amount of dilution. For these use Bicarbonate of soda, vinegar or citric acid, which is safe. Until next time, BW, Nik.

Article 89 – ‘Design: a discussion’ Part 8

Hi welcome to Taiga Bonzai, in this article the last in the discussion on design, we look at the examples of ‘root over rock’ – Sekijoju where the root system encompasses the rock and Ishizuki – ‘root clinging to a rock’.

Disclaimer notice: – this article is not a tutorial on how to produce these two designs, it is a brief explanation on the process of how they are achieved. This art requires certain skills that have been omitted due to their complexity, we are not responsible for any actions taken by others.

Introduction Sekijoju and Ishizuki do take time to construct in order to achieve a balanced composition between the two components tree and rock. Arguably the first step is to decide which to opt for Sekijoju or Ishizuki and to jog your memory Sekijoju is ideal for deciduous varieties as they grow more quickly than conifers, whilst coniferous species can be adapted to both styles. We will use the Ishizuki style for this discussion.

Sekijoju and Ishizuki

Coniferous or deciduous – having made the decision on the species, one has to ascertain it’s possible potential and growth rate, hence a little time spent researching the chosen specimen the better the knowledge. The most important factor at this stage is the size of the root ball, short fat root systems as found on slow growing varieties should be avoided for obvious reasons. The roots need to be robust and extensive more than the total height of the tree; if the chosen specimen does not meet the required measurements, it can be replanted in a deeper pot for a season or two.

So which tree species are suitable, there are many to choose from for example, deciduous can include Ficus aurea, Ficus benghalensis commonly known as the ‘strangler’ fig and banyan tree respectfully as these have extensive aerial root systems that extend to the soil. Others are hawthorn Crataegus, birch Betula nana and cotoneaster family Rosaceae. With conifers these can be juniper varieties of which there are between 50 and 67 to choose from, they include the common juniper J. communis, J. chinensis and J. virginiana.

Whatever the species, the root ball is checked as is it’s configuration a sketch or photograph is is made which is useful when selecting the rock. The distance between the primary and secondary roots is measured, their thickness and pliability especially where they protrude from the base of the tree. This information is written down because it is needed when carving the rock, more time spent on this part of the project reduces the risk of errors later on. When the task is completed, the roots are misted with water and the tree is returned to it’s pot.

Rock choice – there are three main types of rocks igneoussedimentary and metamorphic that are formed by physical changes which include melting, cooling, eroding, compacting or deforming. Common examples are obsidian, granite, pumice, porphyry, calico (laminated sandstone) coquina, (shell limestone) breccia, gneiss, talc schist and serpentine to name but a few of the many that exist. All have different degrees of density, obsidian is soft but prone to fracturing and the shards are extremely sharp. Granite is hard and can be difficult to carve whereas pumice being light weight is easier, see Gaby Pilson’s article on rock types link below.

30 Types of Rock That You Shouldn’t Take For Granite: Pictures and Facts

Carmichael, Robert S. and Klein, Cornelis. “rock”. Encyclopedia Britannica, 19 Oct. 2022, Accessed 5 December 2022.

The hardness of the above rocks as recorded on the Mohs scale of hardness with the number 10 being the hardest are listed here in the order that they are shown. Obsidian 5 – 5.5 – Porphyry – 6 – 7 – Calico (laminated sandstone) 6 – 7 – Coquina (shell limestone) 2 – 4 – Breccia 3 – 6 – Gneiss 6 – 7 – Talc schist 4 – 5 – Serpentine 3 – 6. Others (not shown) include Granite 6 – 7 – Pumice 6 – 6.5 – Quartzite 7 and Slate 2.5 – 4. Before embarking on a rock hunt it would be prudent to research the types of rock that are common in your area, if their appearance does not satisfy the needs then one has to look further afield.

Rock preparation – once the rock candidate is found it has to be prepared by using warm water only, cleaning agents or other chemicals are to be avoided. The rock now has to be sterilized using boiling water for 30 minutes in a clean receptacle in which the rock is submerged. Eye protection is needed as some types of rock are prone to spitting when they break, do not take shortcuts by boiling the rock on the stove because it may explode.

Starting at the rock’s surface (where the tree sits) the root positions are marked out using a permanent marker, the thickness of the roots is checked and depth is noted. This is important because the roots have to just sit in a channel a few millimetres deep no deeper, this is to give the viewer the impression of a natural phenomenon. If this is not done the tree will not correctly fit when anchored down, there should be no gaps between the tree’s base and rock surface.

The trajectory of both primary and secondary roots are marked out, the process is repeated until all the required roots have been marked out. Excessive roots can be removed especially those that interfere or crossover other roots. But not too many as the tree relies on its root system for moisture transportation and sugar reception produced by the foliage. The rock should now resemble a road map full of lines around itself when completed time to begin carving.

The tool needed for this is a Dremel equipped with cutting discs, grinding stones, eye protection and gloves. The Dremel has variable speed and when in motion can cut into the rock with ease depending on the rock’s density, but it can also cut through gloves and fingers; hence a comfortable speed setting is advisable. Carving rocks has its moments, but it is time consuming holding the piece in one hand whilst carving with the other and is often done in stages. Below is an image of our Dremel equipment.

The rock now completed is washed to remove any dust, the channels are inspected for any imperfections and removed if needed. The rock is turned upside down and two wires are fixed to the surface using epoxy resin, these are there to anchor it in it’s intended final ceramic pot. When dry the wires are folded back on themselves so they do not interfere with root growth. Time to marry tree and rock together, plain rafia (not coloured) is needed soaked in tepid water then unravelled. Strands are gathered together and are smoothed out and a knot is tied at one end, the strands are used for binding the roots to the rock.

The tree now out from its container has the soil removed and with the aid of the sketch/photograph the roots are now fitted into the channels, starting at the top working around and down occasionally misting both roots and rock. Wet rafia is tied around the rock to keep the roots in place. Once the task is completed the whole rock is bound again starting at the top working to its base, the rafia is then securely tied.

Grit for drainage is placed in a clean old plastic bucket or wooden box (must have drainage holes) add fresh soil and that which was removed from the tree and it’s container, fertilizer is sprinkled on the medium. (we use granulated pellets) The tree/rock combination is planted just below surface level, watered and left to recover; 2 – 4 years (deciduous) and 3 – 5 years (coniferous) depending on the species.

The approach and methodology in producing the Sekijoju and Ishizuki design discussed here is but one way, other designers will have their own way of producing the same result. And yes we do agree that to venture on an art form such as this takes considerable time, but that is the nature of bonsai or in this case Bonkei. A never ending study of the world’s oldest ‘living’ art form where complicated designs take considerable time to produce, if we are to present a piece of ‘live’ art that is natural in its appearance.

Having read this article there will obviously be a lot of questions regarding these two designs Sekijoju and Ishizuki and we will answer some of them here, you can send us an email ( where you will receive a detailed answer or simply add a comment on our website.

Q. If the Sekijoju style is chosen is there much rock carving to be done if we use the ficus types mentioned or similar species? A. Regardless of the species it is advisable to carve channels to direct the roots in the path you wish them to take.

Q. Can tufa rock be used for these styles? A. Tufa a highly porous sedimentary rock is composed of calcium carbonate, CaCO3 (Limestone) its texture is rough, uneven and full of holes. Although it is not a rock type that we would recommend, there are no rules to say it cannot be used.

Q. Instead of burying the finished piece in a bucket, why not put it straight into its ceramic pot? A. The sculpture will eventually be housed in a shallow pot beit rectangular, oval or round where root run is confined. As the tree has undergone pruning it needs to develop a strong healthy root system therefore, it will develop more quickly in a deeper pot.

Q. Why is the timeline so long? A. Much depends on a tree’s natural growth rate, as stated in the main deciduous develop more quickly than coniferous species, but having said this each particular type of tree beit deciduous or coniferous will have its own growth rate agenda.

Q. Some of the rock types shown are interesting yet a bit too colourful what is the best rock type to use? A. What you are trying to create is an art sculpture that has a natural look a balance between the three entities, tree, rock and pot colour. Porphyry, calico and pumice are fine for deciduous where as granite and pumice are suited to conifer varieties, but you can use whatever you like there are no hard rules.

This concludes the series Design: a discussion, if you wish to attempt these designs we are available to assist, but please remember bonsai requires patience; until next time, BW, Nik.

Article 88 – ‘Design: a discussion’ Part 7

Hi welcome to Taiga Bonzai, in this article we look at some more designs that can either be simplified or complicated due to the artists design, interpretation and perception.

Introduction – an example of a simplistic design giving the appearance of multiple trees is Netsunagari (netsuranari) – often referred to as Raft, sinuous – This style is like the straight-line raft, but the underlying trunk has been subjected to several bends, hence the trees growing up from it do not appear in a straight line.

Design method – a single tree is chosen for this design where the required branches have been selected, the remainder are removed and the wounds sealed either with an appropriate compound or petroleum jelly (vaseline) to prevent infection. Further pruning is required on the remaining branches to thin them out bearing in mind the intended design. (it is a good idea to have sketched this out prior to commencement)

The tree is subjected to an assortment of several bends with the individual branches situated on the outside of each bend, the more severe the bends are; the overall design will give impression of a group of trees. However, be careful when bending as some trees are relatively brittle and are easily snapped, test the tree’s flexibility and carefully manipulate it to soften the rigidness. 3 year old saplings are ideal for sinuous raft design older trees are more difficult due to their girth and heartwood hardness; further bending can be done at a later date.

According to the purists groups of trees in whatever design are always in odd numbers in clumps of 3, 5, 7 and so on, this is to give the impression of a natural look. Some designers bury the trunk below the soil surface to hide the fact that this is a single tree, whilst others have the trunk slightly raised. Sinuous raft is relatively easy to achieve, but it takes planning and thought, the tree is then planted in a large container which allows for root run and development; the top layer of roots above the soil surface can be removed.

Here are two simple examples 1. depicts a group of 7 larch trees notice the height difference in relation to each other tree 4 is the dominant one taking centre stage, 2. shows their position in the container. These two simple sketches are an example of what can be achieved with a sinuous raft design using a single tree. We recommend that you visit other artists including the world wide web; just type the following “Bonsai sinuous raft design” there you will find many examples including visible trunks and those buried.

The more we explore various designs the more complicated they become, we have probably mentioned our first candidate before, but as it is part of the complete known líst in the bonsai catalogue we will include it.

Sokan – Twin or two trunks – two trunks rise from a single set of roots. The base of the trunks generally touch and may be joined to each other up to a short distance above the soil. One trunk is taller and thicker than the other and both are clearly visible from the bonsai’s front. Branches from the two trunks extend left, right and backwards, but not directly toward each other. The images below show a Picea when first purchased and after when the design was near completion.

Three trunk – three trunks rise from separate sets of roots. Trunk sizes are varied, with one dominant trunk being the thickest and generally the tallest. The three trunks are placed so that a straight line cannot intersect all three to minimize symmetry and make the design look as natural as possible.

Gokan – Five trunk – modifying the stylistic constraints of the ‘three-trunk’ style, the five-trunk style allows a second dominant tree to be placed in the design. This tree is subordinate to the largest in size. Larger-numbered group styles (seven- trunk, nine-trunk, forest, etc) also allow a second or third tree to dominate additional groups of trees in the larger design.

Nanakan – Seven trunk – as with five trunk.

Kyukan – Nine trunk – as with five trunk.

Kabudachi (kabubuki) – Clump – in the clump style, three or more (should be an odd number) trunks grow from a single point. The natural equivalent might be a group of trees that have sprouted from a single cone, or a collection of mature suckers springing from the base of a single tree.

Korabuki – Turtle – this style is similar to the clump style, but the trunks do not rise from a fairly flat surface root system. Instead, the ground-level roots form a domed or turtle-back shape where the multiple trunks rise from it.

Ikadabuki – Raft-style (straight line) – these styles mimic a natural phenomenon that occurs when a tree topples onto its side for example, from soil eroding beneath the tree. Branches along the top side of the trunk continue to grow as a group of new trunks. Sometimes, roots will develop from buried portions of the trunk. Raft-style bonsai can have sinuous or straight-line trunks, all giving the illusion that they are a group of separate trees, while actually being the branches of a tree planted on its side. The straight-line style has all the trees in a single line.


Soju – Two tree – in all multiple-trunk styles, conventional bonsai specimens use trees of the same species. As with the twin-trunk style, the two-tree style has a dominant larger tree and a smaller one. The two trees may be set very close to one another as in the twin-trunk style; they may also be set apart as they do not share a single root.

Sambon yose – Three tree – the three-tree design up to nine-tree styles are considered ‘group settings’ rather than forests. The smaller number of trees means that some stylistic goals, such as having no more than two trees in line with each other, may be applied to these bonsai. Trees in groups settings vary in trunk width and height, but generally resemble each other in proportions, density of foliage and other visual characteristics. In the three-tree style, a single tree will be the dominant one. The other two will be smaller and usually differ in size from each other.

Gohon yose – Five tree – as for ‘three-tree’, but there may be two dominant trees. One will be larger than the other and the remaining three will be noticeably smaller.

Nanahon yose – Seven tree – as with five tree.

Kyuhon yose – Nine tree – as with five tree.

Yose ue – Forest – this style describes a planting of many trees, typically an odd number unless too many to count easily in a bonsai pot. The pot has very low sides to emphasize the height of the trees, the pot may be replaced by a flat slab of rock. The trees are usually the same species, with a variety of heights employed to add visual interest and to reflect the age differences encountered in mature forests. (For mixed-species plantings, see the Japanese art of saikei) The goal is to portray a view into a forest and perspective effects, such as placing the smallest trees toward the rear are important in developing a specimen in this style.

Bunjingi – Literati – this style has a generally bare trunk line, with branches reduced to a minimum and typically placed near the apex of a long, often contorted trunk.

Hokidachi – Broom – this style is employed for trees with extensive fine branching, often with species like elms. The trunk is straight and upright and its branches fan out in all directions about 1⁄3 of the way up the entire height of the tree. The branches and leaves form a ball-shaped crown, which can also be very beautiful during the winter months.

Takozukuri – Octopus – an uncommon style, these bonsai have a relatively short, thick trunk topped by several long branches that are contorted into curved shapes, fancifully resembling octopus tentacles.

Trunk and root placement – although the majority of bonsai are planted directly into soil, other styles exist for example, trees planted on rock. A mountain scene – Saikei – uses rock formations and planted with ‘live’ specimens, which is akin to the ancient art of Bonkei. However, according to the founder of this art form Toshio Kawamoto these are living landscapes and not bonsai in the true sense of the word. Nevertheless, rocks are used in bonsai styling for example, ‘root over rock’ – Sekijoju where the root system encompasses the rock. And Ishizuki – ‘root clinging to a rock’, where the root system is less dominant as shown below.

Deciduous root over rock and conifer root slinging to a rock

Slow growing conifers can and do suit these two designs, but they take years to reach their maturity and potential. The world’s slowest growing conifer the white cedar tree found on a lake shoreline in Canada has been officially recorded as growing to a height of 4 inches in 155 years, hence it could not in reality be used. Deciduous varieties grow quicker than conifers and are easier to adapt to the conditions that prevail.

Are these two styles complicated to achieve? tree stylists use various methods to accomplish the desired results, in the next article on ‘Design: a discussion’ the last in this series we show you a step by step method that we use for this design. Until next time, BW, Nik.

Article 87 – ‘Plant husbandry 5’

Hi welcome to Taiga Bonzai, in this article the last in the series we attempt to answer some of the questions that continue to perplex the most learned concerning the demise of flora. In many cases the answer is given in a reasonably short time frame, but there are instances where no definitive explanation can be agreed upon.

Introduction – with the planet constantly evolving evidence exists of events that have resulted, some have been of minor consequence whilst others have caused complete devastation. In 1815 Mount Tambora on the island of Sumbawa in Indonesia erupted, the largest volcanic eruption in history. In 1954, a swarm of locusts invaded Kenya covering an area of 200km2, the estimated density was 50 million individuals per km2 a total number of 10 billion locusts in that swarm. A 15 metre tsunami hit Japan’s Fukushima Daiichi nuclear power plant in 2011 causing a major catastrophe.

Life expectancy – nothing on this planet lasts forever, all flora, fauna including humanoids have a life expectancy and nothing can change this phenomenon. Even planet Earth has a life expectancy, a subject for another time as the implications associated would make this article far too long, but for those of a inquisitive nature we point you to the NEW ATLAS and their scientific author Michael Irving who wrote an article on this subject in March 01 2021. Link below.

Humanoids and fauna – it can be argued that a debate on these two species would make for interesting discussion and much has been written by notable academics including, Alfred Russel Wallace and Charles Robert Darwin works include, The Descent of Man and Selection in Relation to Sex (1871), The Expression of the Emotions in Man and Animals (1872). But, at Taiga Bonzai for the moment we are only concerned with flora and the problems associated.

Flora – all humans especially government officials are responsible for the planet’s well being concerning plant life regardless of the scale. Pests and disease transmitted by our actions either knowingly or not have been in existence for thousands of years, we have written articles on this topic ‘Unseen enemies’ 62 to 66 and 56 ‘Bug apocalypse!’ In the previous article ‘Plant husbandry’ 4 we mentioned the deadly disease Xylella fastidiosa first discovered by plant pathologist Newton Pierce in 1892, a disease that is an aerobic, Gram-negative bacterium of the monotypic genus Xylella. This plant pathogen is transmitted exclusively by xylem fluid-feeding sap insects. 

There is no chemical control for Xylella fastidiosa as is the case for many pests and disease, infected plants are destroyed to prevent the disease spreading further. A downturn in crop production costing vast sums of revenue to the tune of billions. Although many countries are deeply concerned, they just cannot find common ground to find a solution to the problem. Yet they whine, moan and sabre rattle on unimportant trivial items, hence it is difficult to comprehend their logic and justification for such.

The enemy – most common plant pathogens are fungi, bacteria, mollicutes, parasitic higher plants, parasitic green algae, nematodes, protozoa, viruses, and viroids. We will give a brief description on these and their functionality should you encounter them.

Fungi – many people believe fungi are plants, this a misnomer they are neither plants nor animals but organisms that form their own kingdom of life. The way they feed themselves is different from other organisms: they do not photosynthesize like plants nor do they ingest their food like animals. Fungi can be deadly poisonous as in the ‘Death cap’ Amanita phalloides variety and is the world’s most toxic mushroom. It contains alpha-amanitin which is responsible for causing liver and kidney failure.

Death cap fungi

Bacteria – there are both beneficial and pathogenic, beneficial bacteria are involved in such diverse processes as digestion in animals, nitrogen fixation in the roots of certain legumes, the decomposition of animal and plant remains and sewage disposal systems. Pathogenic bacteria called fastidious vascular bacteria grow in either the xylem or phloem tissues and interfere with the transport of water and nutrients in the plant vectored by sucking insects such as leafhoppers, planthoppers and psyllids.

Mollicutes – are parasite in the class of bacteria distinguished by the absence of a cell wall. The word ‘Mollicutes’ is derived from the Latin mollis and cutis. Individuals are very small, typically only 0.2–0.3 μm in size and have a very small genome size. The best-known genus in the Mollicutes is Mycoplasma colonies which show the typical ‘fried-egg’ appearance.

Mycoplasma image courtesy of

Parasitic higher plants and Green algae – Hemiparasites often referred to as water parasites, do injure their host plants, absorbing water and mineral nutrients from them. They possess chlorophyll and can manufacture their own carbohydrates by photosynthesis. Green algae are a foliar disease most commonly seen in warmer climates or in greenhouses. The main organism is Cephaleuros virescens, a green parasitic alga whose usual hosts are plants with leathery leaves such as litchi, magnolias, hollies, rhododendrons and viburnums.

Parasitic green algae on guava Image courtesy of Scot Nelson

Nematodes – often called ’roundworms’ are the most numerous multicellular animals on earth. A handful of soil can contain thousands of the microscopic worms many of them parasites of insects, plants or animals. Free-living species are abundant, including nematodes that feed on bacteria fungi and other nematodes. There are nearly 20,000 described species classified in the phylum Nemata many of which are associated with disease.  


Protozoa – are a group of single-celled eukaryotes either free-living or parasitic that feed on organic matter such as other microorganisms or organic tissues and debris. They come in many different shapes and sizes ranging from an Amoeba which can change its shape to Paramecium with its fixed shape and complex structure. Some are parasitic meaning they live in other plants and animals including humans where they cause disease. 

Protozoa Image courtesy of Frank Fox Microbiology Society 

Viruses, and viroids – a virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms from animals, plants and other microorganisms, including bacteria and archaea. Viroids are small single-stranded, circular RNAs that are infectious pathogens. Unlike viruses, they have no protein coating. All known viroids are inhabitants of angiosperms (flowering plants) and most cause disease.

Cowpea mosaic virus Image courtesy of Thomas Splettstoesser ( 

The hidden menace – in part 4 of this series we stated that “the problem with disease is that it cannot in reality be detected until there is visible evidence, either insect damage or that of fungi and canker.” Here is an example of our meaning, approximately 4 years ago we obtained a 3 year old Sea buckthorn plant Hippophae in the family Elaeagnaceae.

Sea buckthorn Hippophae

The aim was to train it into a Bunjin-gi literati style, in the first winter we did some work to the trunk and foliage right hand image. We decided to take our time with the design and make gradual changes so as not to stress out the tree and the cuttings were planted in different containers. All was progressing according to plan until beginning of summer 2022, when we discovered the trunk was coated in a white fungus, leaf drop had begun and remaining leaves showed signs of chlorosis. We knew the end was nigh for this plant hence it was destroyed.

Naturally our readers will want answers as to the tree’s demise so we will answer them here:

Q. what disease killed the tree – A. Verticillium wilt sp. was the culprit for which there is no effective treatment

Q. did the problems come from the soil medium, incorrect watering and bad position – A. when the plant was purchased the original soil was removed and the plant washed, it was re-planted in the same soil medium we use for all our deciduous species and we have no problems with it. Watering was twice daily in the summer and less in the winter; the tree had a good sunny position with plenty of light and air movement

Q. are any of your other trees showing signs of infection and what about the cuttings you took, A. no they are thriving very well and the cuttings were taken from the original plant after it had been repotted nevertheless, we will keep a watchful eye on them

Q. if there were no problems at your end how did the disease get there A. Verticillium wilt can lie dormant until the conditions are such that is activated, it can spread rapidly killing sea buckthorn varieties in two years with the variety Clara being the most infected; we are of a conviction that this was the case in this instance – it was already there when we obtained it.

Sea buckthorn is a plant that has few diseases. Among the diseases that can occur in sea buckthorn plantation we mention: verticillium wilt (Verticillium albo-atrum, Verticillium dahliae), Fusariosis (Fusarium sp.) and decay caused by fungi from the genera Phytium, Alternaria and Botrytis. Verticillium wilt can occur quite often in sea buckthorn plantations, the pathogen Verticillium sp. being so dangerous is able to kill the shrubs very quickly.

This series ‘Plant husbandry’ (1 to 5) has been a discussion on plant care and also on plant pathology and we trust that you have found the content useful. This website Taiga Bonzai has many more articles on various topics relating to bonsai and horticulture in general, feel free to browse at your leisure; until next time, BW, Nik.

Article 86 – ‘Plant husbandry 4’

Hi, welcome to Taiga Bonzai in this article we discuss some of the many reasons why plants give the appearance of health and vitality one moment then suddenly show signs of decline the next; a problem scientists and horticulturists have been trying to solve for eons.

Introduction – there are countless reasons why plants die and to attempt to explain the cause and effect would result in volumes of the written word therefore, we look at some of the most common and those uncommon. These include the seed or plant, soil medium, water table, pests and disease most of which can be found in our articles and we will point them out as we proceed with this discussion.

Seeds – in nature plants have various ways of dispersing their seeds on the wind, by animals and birds that consume and dispense them through their digestive system. Such seeds released from the parent plant are in what is termed as a dormancy stage and dormancy is a natural state of being in many plants, its function is to ensure that the seed will germinate at an appropriate time. However, seeds can remain in a dormant state and fail to germinate although conditions, temperature, water and light are in ample supply.

Why this phenomena occurs can be attributed to a seed’s morphological and physiological requirements, because seed dormancy is able to originate in different parts of the seed for example, within the embryo or its coating – the shell or husk. Dormancy is deemed not as a constant, but as a variable because it is a common phenomenon encountered in a large variety of trees. However, it should be noted that not all seeds have embryos hence they will never germinate.

It can be argued that seeds are delicate in their form and their is evidence to support this theory for example, in (commercially grown) vegetables and various fruit species, because their ‘shelf life’ is short. However in the main seeds collected from the wild are robust and quite hardy able to withstand high and low temperatures and can be stored in the right conditions for long periods of time; providing they have not been attacked by pests and disease. See article 60 ‘Germination! – no guarantee’

Soil mediums – are prepared to suit the plant beit ericaceous (coniferous) or organic (deciduous) and should be a composition with good drainage allowing the roots especially feeders to travel in search of nutrients and moisture; compacted soil mediums are detrimental to the plants well being. See articles 27 and 28 ‘The pH factor’ which discusses various soil compositions. A question often asked is “does the soil have to changed on a regular basis” in short the answer is no, because a teaspoon of soil is estimated to contain up to a billion bacteria cells that work to maintain the soil condition. Adding a small amount of fertilizer occasionally helps and the plant can survive for years in the same medium.

However, much depends on the type of plant regardless of the species, if growing from seed then the plant will require a soil medium to help the initial growth stage for example, John Innes no. 1 or similar brand. When the plant has developed sufficiently i.e. a few pairs of leaves it is re-planted in a soil medium that is more appropriate, this is done to slow the growth rate otherwise the plants becomes ‘spindly’ tall, or thin and will take some considerable time to gain girth. Plants in this condition are easily stressed and susceptible to attack because it’s defences are weakened, the first signs are chlorosis (yellowing of the leaves) and leaf drop.

Water table – in the main most trees dislike their roots soaking wet nonetheless, there are exceptions to this consensus for example, the following permanently reside in wet conditions. Pumpkin Ash, Fraxinus profunda Sweetbay Magnolia, Magnolia virginiana Willow, Salix Mangrove, Rhizophora mangle Bald Cypress, Taxodium distichum Water Tupelo, Nyssa aquatica River Birch Betula nigra and Pin Oak Quercus palustris. The water pH ranges from acidic to saline and plants living in such conditions are able to thrive quite well, but the majority of others species cannot tolerate these extremes.

If you have the ability to harvest and store rainwater this is preferable, alternatively if you rely on the household tap, the water condition will depend on the supplier and the chemicals used to treat it for example. Fluoride (F) banned in many countries is a neurotoxin and endocrine disruptor, able to damage the thyroid gland and interfere with bone formation. Chlorine (CI) a strong disinfectant added to drinking water as a purification technique. Other chemicals can include Mercury (Hg), Arsenic (As) used in a multitude of industrial processes, Lead (Pb) a major toxin that still exists due to corroded piping systems. To read the problems with tap water and how to treat it see articles 35 and 36 ‘A teaspoon of vinegar’.

Pests and disease – the most common of pests and disease derive from insects including: Aphids Aphidoidea, Scale Coccoidea, Mealybug Pseudococcidae, Sawfly Septentrionalis and Red spider mite Tetranychus urticae. The latter difficult to see with the naked eye as it resides in the soil, the only immediate way of detection is via the very fine webs they weave. Plants infected with red spider mite often fail to survive yet they can be saved. Remove the plant from its container and discard all traces of soil, the whole plant is sprayed with horticultural soap; re pot the plant, water, isolate and keep a watchful eye out so the problem does not reoccur.

Unfortunately the predators that usually protect our plants are disappearing at breakneck speed due to loss of habitat caused by the idiosyncratic lust for urbanisation. Farmers and land holders are being paid not to produce crops but to turn their fields into wildlife havens to encourage the return of the predators. This is akin to ‘shutting the stable door after the horse has bolted’ a ludicrous policy considering the present world crisis.

(a) During World War II (1939 – 1945) many governments mandated that more produce be grown to feed those at the front line, those unable to enlist for whatever reason were forced to endure rationing which lasted until 1954. Meadows and wildlife havens were turned into arable land and although the effects of this were not apparent at the time; it was the beginning of the end for the bug world. Evidence of this can be substantiated in article 56 ‘Bug apocalypse’

(b) On March 25th, 1957 France, West Germany, Italy, the Netherlands, Belgium and Luxembourg signed a treaty in Rome establishing the European Economic Community (EEC), also known as the Common Market. As the years rolled by other countries also signed up and soon there was an abundance of food including butter mountains, milk and wine lakes, gluts of potatoes, apples and other fruits. Did they give it away to the poor or countries facing drought and famine – NO – what could not be poured away was disposed of in disused mine shafts

(c) The green and pleasant lands are now a bygone era, forests have and are being cut down, an area the size of Wales 20,779 km² (a country in southwest UK) is being removed on a daily basis in the Amazon. The meadows that existed are now under housing estates, rivers are polluted and the air quality is deteriorating. The friendly bugs have gone and it is doubtful they will return and the crop harvests GMO or organic will devastated by marauding invaders many whom are immune to pest control see article 20 ‘Pests and diseases’

(d) Remember covid 19 where 6.3 million needlessly lost their lives, the world’s governments could not solve that problem and the disease is still apparent; what are they doing now, placing sanctions that are a reaction of mass childish hysteria; which has backfired. In the immortal words of ‘Ja Ja Binks’ the Gungan outcast in ‘Star Wars’ (plated by actor Ahmed Best) “Weesa in deep do do” and the level is rising. Is it not high time the bungling cretins of the EU and others be held accountable for their stupid mismanagement and decision making. We leave you with this thought; “The folly of the mindless maketh the intelligent weep.”

The problem with disease is that it cannot in reality be detected until there is visible evidence, either insect damage or that of fungi and canker. Science has told us that microorganisms can exist in a single-cell form or a colony like bacteria and fungi and although they are often associated with dirt and disease, most microbes are beneficial. But as we are aware there exist those microbes, fungi and pathogens that have lethal potential here a few examples.

Armillaria mellea is a parasitic fungus doing immense damage to forests, it attacks both coniferous and broadleaf trees. By the time the fruit bodies are in evidence, the damage done internally is usually so great that the tree is doomed. It is widespread in northern temperate zones including North America, Europe and Northern Asia also in South Africa. Trees that are attacked become parasitized. The foliage becomes sparse and discoloured, twig growth slows down and branches may die back. There are no known fungicides or management practices that will kill Armillaria mellea after infection without damaging the infected plant.

Armillaria mellea

A plant canker is a small area of dead tissue, which grows slowly, some of these are of only minor consequence, but others are ultimately lethal and therefore, can have major economic implications for agriculture and horticulture. They are caused by a wide range of organisms including fungi, bacteria, mycoplasmas and viruses. The majority of canker-causing organisms are bound to a unique host species or genus, but a few will attack other plants. Fungicides or bactericides can treat some cankers, often the only available treatment is to destroy the infected plant to contain the disease. The Butternut canker (shown below) is a lethal disease affecting Butternut trees for which there is no cure.

Image courtesy of wikipedia

Borers are perhaps the most harmful to trees, The Asian Longhorned beetle Anoplophora glabripennis native to eastern China, and Korea has been introduced into the United States, where it was first discovered in 1996, and in Canada and several countries in Europe including, Austria, France, Germany, Italy and UK. This beetle is believed to have been spread from Asia in solid wood packaging material. A. glabripennis primarily infest maple, poplar, willow, and elm trees. In the United States it has attacked birch, katsura, ash, planes and Sorbus; In Canada on maple, birch, poplar and willow and in Europe on maple, alder, birch, hornbeam, beech, ash, planes, poplar, Prunus, willow and Sorbus.

The Bronze Birch borer Agrilus anxius is a wood-boring Buprestid beetle native to North America numerous in warmer parts of the continent where it thrives. It is a serious pest on birch trees Betula frequently killing them and if this insect came to Europe there would be no hope for Birch forests as the trees have no resistance against this species of insect; hence the effect on Scandinavia’s Birch industry would be devastating.

Sirex woodwasp Sirex noctilio a species of horntail native to Europe, Asia and North Africa is an invasive species in other realms including Australia, New Zealand, North and South America and South Africa where it has become a significant economic pest of pine trees especially Pinus radiata. The wasp can attack a wide variety of pine species, although some species seem to be more susceptible than others and stressed trees often are attacked. It is believed that this insect was introduced on unprocessed pine logs imported from Europe. 

Sirex woodwasp Sirex noctilio

There are many other pests and disease to contend with several of which we have discussed in the articles 62 to 66 ‘Unseen enemies’, but one that is now devastating the horticulture industry is Xylella fastidiosa. This is a deadly bacteria that attacks economically important crops such as olive, citrus, plum trees and grapevines. Since 2015, it’s been rapidly spreading from the Americas to Europe and Asia. Once the disease infiltrates a plant, it is there to stay, it starves the plant of water until the plant dies or becomes too weak to grow fruit. 

X. fastidiosa costs $104 million per year in wine losses in California and in Italy the bacteria has led to the decline of 180,000 hectares of olive groves destroying many centuries-old trees; a loss of €390 million over three years. X. fastidiosa constitutes a threat not only to Italy but to all the Mediterranean region’s economy.

Image courtesy Wikipedia

X. fastidiosa is not known to be in the UK however, there have been outbreaks of the disease in mainland Europe in France, Italy and Spain. Portugal confirmed its first case in 2019 on lavender hence, the UK Government is concerned about how to prevent the disease being accidentally brought into the country on imported plants. In 2020 Lord Framlingham a Conservative peer asked the Government what the UK’s regulations are regarding X. fastidiosa.

UK regulations were to introduce measures to strengthen the protection of plants from certain pests and diseases, including Xylella. They were made under article 52 of the EU Plant Health Regulation allowing the UK to take additional temporary national measures if they inform the European Commission and put forward a technical case to request EU measures against a specific pest, but those measures have not or will not be introduced in time to mitigate the risk concerned.

Moreover, the UK Government has argued that current EU emergency measures on Xylella do not address risks highlighted in the UK’s pest risk analysis on the disease. In particular, it is not clear if or when the EU emergency measures will be reviewed to address these risks and ensure a greater degree of assurance of disease freedom, in relation to plants of those species being moved in the EU and introduced from third countries. As such, there remains an unacceptable level of pest risk and this instrument introduces national measures under article 52, in the absence of EU requirements.

It would appear from the above debate that various governments cannot not find common ground to solve the problems of pest and disease control, they are only concerned with their own interests instead of working for the good of all. The problems are out there and they need to be addressed as science has told us, failure to do so will result in dire consequences for all. In the last part of this series ‘plant husbandry’ 5 we conclude this topic with some unanswered questions, until next time, BW, Nik.

Article 85 – ‘Plant husbandry 3’

Hi, welcome to Taiga Bonzai in this article we look at the question of health and vitality regarding trees/plants in our care, many of our followers have asked us to give a deeper understanding of the importance of plant care and maintenance.

Introduction – plants regardless of their origin be it from a nursery, the wild, cuttings, seed and grafting etc destined for bonsai are susceptible to loss of health and vitality if not afforded care and attention. Although there are a number of factors why this happens, the main five to consider are – 1. plant research 2. soil medium 3. water 4. position or location. 5. pests and disease will be discussed in the next article ‘Plant husbandry 4’ because of its intended length.

Research – today due to trade agreements we are able to obtain a variety of plants from other realms that can be found at various outlets. Many displayed give the impression of pristine health and vitality however, if purchased the plant/s will be transported to an environment far removed from that of origin. These new conditions are completely alien, because of environmental changes in heating, lighting, air circulation and water especially if the plant is from a temperate zone. Hence conditions must be adapted to suit their needs not the other way round.

When looking for potential plants from a vendor the first action is a thorough examination, if possible remove the plant from its container and examine the root ball for signs of healthy growth and/or damage. It is a good idea to have a ‘pocket sized’ test kit with you to ascertain the soil pH. Inspect the trunk, branches and foliage, look for signs of damage, discolouration of leaves and check for unwanted pests; it is more likely than not that some will exist usually the ones not visible to the naked eye.

Next read the label (that is if there is one) it will tell you it’s common name and possibly its family and species in latin, but that is usually about all. Consult the vendor ask where the plant in question originated, if the answer given is acceptable, move on to the next stage which is transportation and isolation/quarantine failure to do the latter can result in some unwanted nasty surprises for example, cross contamination, infection and demise. We have all had experience of this at some point or another.

If collecting from the wild the examination process is much the same, but with a little more thought. The first question is does the plant have any possible potential bonsai characteristics for example, from the classic design list Chokkan, (formal upright) Moyogi, (informal upright) Sokan, (twin trunk) Bunjin-gi, (literati) Kengai (cascade) and Shakan (slanted) etc. Check the distance between the branches if they are too far apart then the proposed specimen in reality has no potential and even hard pruning will not necessary force the plant to produce new growth to fill the voids although much depends on the species; if in doubt walk away.

The following bonsai class includes Komono 15 – 26cm, Katade Mochi 25 – 46cm, Chumono Chui 40 – 90cm, which are common sizes when collecting from the wild and the root spread will vary considerably depending on a particular species, age and rate of growth. The general rule of thumb when assessing the area of root spread (although it is not accurate) is to imagine the tree in a horizontal position left or right. Visually mark this position noting where the tree’s apex would be and place a coloured marker, then measure the distance from the apex to the centre of the trunk this is the radius.

Whatever the measurement is, will be doubled which will give an idea of the root spread area it applies to all points north, south, east and west mark these points with a stick or flag; this gives an indication of the area to be excavated. Therefore, if you were trying to harvest a potential Omono Dai 76 – 122 cm specimen for example, the work involved would be tremendous because you need as much of the root ball as possible, otherwise the plant may not recover from its ordeal. Do not cut corners, the roots are vital to the plants survival especially the feeder roots.

Moreover, not only do you need permission to harvest the tree, you have to put the land back as you found it. If you have little experience in tree harvesting get a professional collector to undertake the work and yes it will cost money for this service; the tree’s health and welfare are more important than your desires; think before you act – if in doubt walk away.

However, far too often greedy people try to cut corners and undertake tree harvesting themselves on private and public land including parks and other protected areas without permission. Because they are aware of the fact that without experience they cannot be granted a licence. The consequences of this despicable selfish behaviour is that not only will the tree suffer and die, it deprives the public of natures beauty. Below is an image of a scots pine devastated by a collector whose non professional actions have caused the demise of this potential Yamadori bonsai.

200 year old scots pine destroyed

There are other factors to be taken into consideration when harvesting and again much depends on the species, some trees depending on the terrain may appear stunted almost dwarf like. For example, the root system of the dwarf common juniper (Juniperus communis) can travel many metres under rocks, through cracks and crevices and are impossible to excavate. As are the most sought after Yamadori often located in mountainous areas whose roots have to travel long distances through rocky terrain in search of nutrients and minerals due to poor soil conditions. The specimens mentioned here cannot be harvested for good reasons and should be left alone.

However, all is not lost when attempting tree harvesting, it can be done in stages if you have the patience and build up the skills before hand. A good way to learn is if you know of someone a neighbour, friend relative or landscape artist and ask to assist them for a day or two, in return for your labours ask for the shrubs or small trees that will normally be discarded. Be up front and tell the person/s that you are a bonsai student and need the plants to further your knowledge and that you have no intention of selling them.

Once you build your knowledge and expertise the road ahead does not get easier it gets harder especially If you are in difficult terrain. The procedure is always the same thorough examination of the proposed candidate and inspection of the surrounding area be it a bog, roadside ditch, open field or rock strewn landscape and all will present problems that must dealt with accordingly. Make sure you have the correct tools and apparel for the task. Carefully excavate and investigate the root system to ascertain, which roots can be cut and which to leave. See article 83 ‘Plant husbandry 1’

Remember the tree needs its root system for the transportation of moisture and reception of nutrients. In addition, you can remove unwanted foliage to maintain a balance between top growth and roots. When the operation has been carried out, the soil is carefully replaced and the tree is watered and left to recover for another year. On return checks are made for new root growth and if possible, the process is repeated on other inaccessible roots. The collector returns the following year, inspects the root system and if all is well harvests the tree. There are many videos on tree harvesting where you can get some idea of the undertaking, but be warned – not all collectors are professional. Here are two channels that might be of interest that are related to this subject.

Gro Bonsai –

Terry Erasmus –

The final class include Omono Dai 76 – 122 cm and Hachi-Uye known as six handed growing to heights of between 102 – 152cm and Imperial the largest 152 – 203cm and are arguably the most majestic of all Bonsai seen in the Japanese imperial gardens and other prominent arboretums around the globe. When maintenance is due to be carried out heavy cranes and moving equipment is required plus a small army with many hands that work carefully and quickly so as not to give undue stress to the tree.

Research of all plants is crucial, failure to do so only ends in misery, loss of time and money. Most people carry smartphones connected to the world wide web, enter the plant’s name and find the requirements to ensure it’s health and well being for example. Soil medium composition ericaceous or organic, the pH factor, correct watering, position for example, full sun or shade and what pests and disease is the plant susceptible to; this is the basic information required. Alternatively go to this web site where you can find all the information you need, alternatively contact us direct email is in the about tab.

Soil mediums – these range from ericaceous, (acidic soils) neutral to alkaline (soils with a clay/chalk structure) the scale shown here indicates the divisions between the different soil types. Most plant species live in soils from 4.0 through to 9.0 although there are species of plants that thrive outside of these boundaries. A pH chart for most bonsai plants can be found on this site indicating which soil type to use; Article 27 ‘The pH factor’ (Part I.)

It is not only the pH level that is important, soil medium and the components combined within play an important part in the medium’s structure. There are many types of soil compositions ranging from acidic to alkaline including: Peat – Sandy – Clay based – Chalk based – Silt – Loams – All purpose – Organic and Inorganic. We have written articles on this subject and the information you need can be found in article 28 ‘The pH Factor’ (Part II). In addition, another point to consider is that the soil medium must have good drainage – wet soils are detrimental to the plants health.

Water – is a very important factor as its chemical components can either allow the plant to thrive or not, because the differences between rain water predominantly neutral and what comes out of the household tap has an effect on bonsai trees and shrubs. For example, coniferous species require rain water or water that has been treated, we researched this topic, experimented and found that by adding vinegar to tap water neutralises the alkalinity. (1 teaspoon of vinegar to 7 litres water) See articles 35 and 36 ‘A teaspoon of vinegar parts 1 and 2′.

Position or location – all plants need natural light to photosynthesize meaning the production of sugars that are transported to the roots. With plants that require and outdoor location, full sun, part sun and shade or full shade should be positioned where they receive the benefits they require. Indoor or temperate plants should positioned in a south facing area preferably with good light and ventilation, although this is not always possible due to the position of the dwelling.

If the light source is inadequate you need either to find another location or add a suitable lighting fixture. We have researched this topic and experimented with various lighting systems over a three year period to ascertain their longevity and cost, the end result was a preference for the light emitting diode (LED) which NASA is experimenting with for the production of space horticulture. The following article is a comprehensive paper, see article 03 ‘Lighting for bonsai’.

Other factors detrimental to the health and vitality of plants due to stress are: excessive pruning to the root ball and foliage, splitting, channeling, grooving, hollowing, extreme sharimiki/jin application and extravagant bending of branches although much depends on the plant species. At this juncture we can only reiterate that the key word is and remains ‘Research‘ before undertaking any work, until next time, BW, Nik.

Article 84 – ‘Plant husbandry 2’

Hi welcome to Taiga Bonzai, we have discussed what happens below ground with the root system and its functionality, in this article we concentrate on what occurs above ground in the foliage and its production of sugars and starches that feed the root system.

Introduction – photosynthesis is a process used by plants to convert light energy into chemical energy through cellular respiration that can later be released to fuel the plant’s activities. Some of this chemical energy including sugars and starches are synthesized from carbon dioxide and water and stored in carbohydrate molecules. In most cases oxygen is also released as a waste product which stores three times more chemical energy than carbohydrates. 

Photosynthesis process

Light energy – although various species of plant perform photosynthesis in different ways, the process always begins when energy from light is absorbed by proteins in a reaction centre, which contain green chlorophyll and other coloured pigments referred to as chromophores. In plants, these proteins are held inside organelles called chloroplasts, that are most abundant in leaf cells, while in bacteria they are embedded in the plasma membrane.

In these light-dependent reactions, some energy is used to strip electrons from suitable substances including, water and oxygen production. The hydrogen freed via the division of water is used in the creation of two further compounds that serve as short-term stores of energy, allowing its transfer to drive other reactions. These compounds are reduced nicotinamide adenine dinucleotide phosphate (NADPH) and adenosine triphosphate (ATP) namely the ‘energy currency’ of cells.

In plants sugars are synthesised by a subsequent sequence of light-independent reactions referred to as the Calvin cycle. It is here that atmospheric carbon dioxide is incorporated into existing organic carbon compounds, such as ribulose bisphosphate. By using the ATP and NADPH produced by the light-dependent reactions, the resulting compounds are then reduced and removed to form further carbohydrates, including glucose.

The light spectrum – in article nos ’03’ ‘Lighting for bonsai’ we discussed our 3 year research program on different forms of lighting that are used in horticulture production. The reason for this was to find a lighting source that could mimic the spectrum. Included were traditional incandescent bulbs – Tungsten (now removed from the market replaced by energy-saving bulbs) CFLs, (Compact fluorescent lamp) Halogen, HID, (High intensity discharge) HPS, (High pressure sodium) and LED, (Light emitting diode) the latter the only one that could come close to mimicking the light spectrum. 

If we look at the light spectrum shown above, we see a band of colour change from ultra 400 nanometers to infra at 800 nanometers. It is argued in some quarters that plants use the whole light spectrum for growth, this maybe the case in some instances, but in reality plants only use ultra to cyan for growth and red to infra for flower and fruit. The area between ultra and infra approximately 525 to 625 nanometers the middle part of the spectrum called white light is not that beneficial to plants, which has shown to be the case in NASA’s experiments for growing plants in space.

Nutrient movement – soil mediums play an important role in how plants receive nutrients, if the structure is compacted it will severely limit the roots ability to move toward nutrients in addition, it also restricts water movement thus preventing root growth. Properly prepared soil mediums allow for root-run, water movement and drainage, for more on this topic see article nos ’09’ ‘Bonsai soils’. As the roots pump water to the foliage the leaves in return send sugars and starches to the roots, this cooperation between root system and foliage ensure growth and vitality.

The xylem showing nutrient (white) and water (blue) movement

Thus far we have discussed the functionality of the root system below ground (article 82) and now what is above ground – the foliage and its purpose – photosynthesis and transportation of sugars and starches and the importance of light. Although these are crucial elements in bonsai and horticulture production, there are other aspects to focus on including heating, ventilation and water.

Plant husbandry – plants including bonsai endemic to particular regions subjected to the elements of the seasons do not require heating. Established plants will adapt their growth cycles as they have for countless eons moreover, ventilation is not a problem as there is always a constant circulation of air. However, plants from temperate zones (often referred to as indoor plants) do require some form of warmth during the cold times in order to survive and this can cause problems.

For decades building designers and heating engineers have tried to conceal heating systems including radiators by positioning them where they are inconspicuous, usually affixed below windows covered by a shelf. People keep plants on these shelves as it is probably the only natural light source available, but this location is detrimental. (a) Because the constant heat evaporates moisture from the soil medium too quickly and (b) constant watering saturates the root system, which can cause problems such as chlorosis affecting the plants health and vitality.

Turning down the thermostat may help in reducing moisture loss but the area is now at a lower temperature, which can have an effect on the plant’s ability to thrive; the average temperature for most temperate indoor plant varieties is 22 to 26° Celsius. If one moves the plant away from the window area then the problems of light loss becomes apparent, which lessens the performance for photosynthesis and healthy growth; is there a solution to this problem? – Yes move the plants away from direct heat.

Returning to the article nos ’03’ ‘Lighting for bonsai’ you can find many references to different lighting fixtures for example, the Hydroponic full Spectrum CFL grow light bulb a 105 Watt 5500K perfect daylight balanced pure white light bulb H105 costing $24.99. Although this may seem a bargain, do not be tempted because the manufacturers claims are incorrect. These cheaper versions of this type of light bulb are not full spectrum, they only emit red light and not the blue light (ultra) needed for growth.

In addition, much depends on the number of plants in your collection, if large or spread out you will probably need more than one bulb because the footprint (the light arc) of one is not wide enough to cover your plant display. Suspending the lights higher to create a larger light arc reduces the power of the lumens, the closer the light source to the plants the more beneficial it becomes. Plus the added fact that you will have to purchase or create some sort of apparatus to suspend the light fixture.

Moreover cheap bulbs may seem an inexpensive solution but many do not have aluminium heat sink plates and get extremely hot, hence fittings to the power source have to be ceramic not plastic for obvious reasons. Therefore, we urge you to research your needs thoroughly before contemplating any purchase, because the cheaper route is not always the best; it may cost more. The image below is one of our LED lighting fixtures purchased in 2016, it is in use from October to May (8 months for 14 hrs per day) and to date (October 2022) there have not been any problems.

Full spectrum LED light setup

Water – it can be agreed that the only water safe for all plant species is rain water due to the fact that it is pure, soft, uncontaminated and sweet to the taste and if collected in containers can be used without repercussions. However, it is not always possible to collect it if one lives in dwellings where rules restrict this practice, the only other option is to use what comes out of the household tap and this is where the problems begin.

Municipal water or domestic water is full of chemicals including Fluoride (F) that was introduced in the 1940’s to assist in reducing tooth decay, Chlorine (CI) a strong disinfectant added to drinking water as a purification technique. Other chemicals found in tap water include, Mercury (Hg) a by product of mining and industrial practises, Arsenic (As), Lead (Pb) and Glyphosate that are major toxins that can do irreparable damage. To find out more on the problems in using domestic water even for human consumption, read the articles nos ’35’ and ’36’ ‘A Teaspoon of Vinegar’ and ‘A Teaspoon of Vinegar’ Part 2.

If domestic water is all that is available it can still be used but it has to be treated, you will need two plastic containers enough to hold 7 litres of water each. Mark one container ‘alkaline’ for deciduous varieties and the other ‘acid’ for coniferous. The ‘alkaline’ container can be filled from the house tap, but must be left to stand for at least 2 days before use. In the ‘acid’ container add a teaspoon of vinegar (the type does not matter) then fill with water from the same tap, this also has to stand for 2 days before use. The vinegar in the water reacts with the alkaline particles creating black streaks these are not harmful, but it is not advisable to consume it.

Black algae in vinegar treated tap water

Your untreated ‘alkaline’ water is for temperate plants varieties only, never coniferous or any other acid loving species including Magnolia, Azaleas and Rhododendron, use the treated ‘acid’ water for these. In addition, you can use the ‘acid’ solution on temperate and other deciduous plants occasionally, if in doubt read the article nos ’27’ ‘The pH factor’ part I or contact us direct, email address is in the about section under our name and logo. Until next time, BW, Nik.

Article 83 – ‘Plant husbandry 1’

Hi, welcome to Taiga Bonzai, we receive many questions on ‘Plant husbandry’ for example, ” If we plant a seed it will probably germinate, but it would be good to know a little more science on the subject for better understanding.” Okay, we will discuss these issues in the next 4 articles, but as extensive research has already been written (and we will point out the appropriate articles) the discussions will be in brief.

Introduction – germination is defined into two categories Epigeal (above ground) and Hypogeal (below ground) as a seed germinates the first structure to emerge from most seeds is a root from the embryonic called a radicle, this primary root is referred to as a taproot. Smaller lateral roots (secondary roots) arise from the taproot which in turn produce even smaller lateral roots (tertiary roots) these serve to increase the surface area for water and mineral absorption.

Epigeal germination
Hypogeal germination

The above images show the stages of germination from the radicle to the first true set of leaves and needles respectfully. Cotyledons are the first leaves produced by plants, but they are not considered true leaves and are sometimes referred to as ‘seed leaves’, because they are actually part of the seed or embryo of the plant. These seed leaves serve to access the stored nutrients in the seed feeding it until the true leaves develop and begin photosynthesizing.

Root growth – roots grow in length from their ends only, the very tip of the root is covered by a thimble-shaped root cap called the calyptra, which protects the growing tip as it makes its way through the soil. Behind the root cap lies the apical meristem here cells are produced, some are added to the root cap, but the majority are added to the region of elongation, which lies just above the meristematic region. Above this lies the region of maturation where the primary tissues of the root mature, completing the process of cell differentiation that actually begins in the upper portion of the meristematic region. (shown below)

Aerial roots – some roots called adventitious roots arise from an organ other than the root, for example from a stem or leaf. These adventitious roots often referred to as aerial roots can hang long distances before coming into contact with the soil or remain dangling in the air. Some of these including the Screw pine and banyan do assist in supporting the plant in the soil, aerial roots are the primary means of attachment to non-soil surfaces such as buildings, rocks and other plants for example. The Ficus watkinsiana family Moraceae (strangler fig) named for their pattern of growth upon host trees, which often results in the host’s death.

Image courtesy of By Poyt448 Peter Woodard
Ficus watkinsiana on Syzygium hemilampra, Australia

A number of other specialized roots exist among vascular plants for example. Pneumatophores an aerial root specialising in gaseous exchange are commonly found in mangrove species that grow in saline mud flats. These are lateral roots that grow upward out of the mud and water to function as the site of oxygen intake for the submerged primary root system.

Other root systems – the roots of certain parasitic plants are highly modified into haustoria, a rootlike structure that grows into or around another structure to absorb water or nutrients, mistletoe and members of the broomrape family are good examples of this. Many plant roots also form intricate associations with mycorrhizal soil fungi, a number of non-photosynthetic mycoheterotrophic plants including the Indian pipe rely exclusively on these fungi for nutrition.

Root functionality – the primary tissues of the root are from outermost to innermost, the epidermis, cortex and vascular cylinder, the epidermis is composed of thin-walled cells and is normally only one cell layer in thickness. The absorption of water and dissolved minerals occurs through the epidermis, a process enhanced in most land plants via the presence of root hairs – slender tubular extensions of the epidermal cell wall that are found only in the region of maturation.

The absorption of water is achieved via osmosis, which occurs because (a) water is present in higher concentrations in the soil than within the epidermal cells, where salts, sugars and other dissolved organic products are contained. (b) The membrane of the epidermal cells is permeable to water but not to many of the substances dissolved in the internal fluid. These conditions create an osmotic gradient, whereby water flows into the epidermal cells, this flow exerts a force called root pressure, that helps drive the water through the roots.

The cortex conducts water and dissolved minerals across the root from the epidermis to the vascular cylinder, then transported to the rest of the plant. The cortex also stores food transported downward from the leaves through the vascular tissues, the innermost layer of the cortex consists of a tightly packed layer of cells called the endodermis, which regulates the flow of materials between the cortex and the vascular tissues.

Why no tap root? – In bonsai many practitioners remove the ‘tap root’, but the ‘tap root’ enables stability and water absorption so why remove it? The following deciduous species have rather large tap roots Oak Quercus, Black Walnut Juglans nigra, Silver Fir Abies alba and White Mulberry Morus alba. Coniferous species contrary to popular belief do not have long tap roots, their lateral roots and tertiary roots spread outward and grow downward which gives stability however, there are some exceptions including the Long Leaf pine Pinus palustris that have large tap roots.

In order for these and many other species of tree to become bonsai the roots have to be pruned and the more vigorous the root growth the more pruning is required. In Japan and China young trees are planted in deep pots to encourage root growth and after a few seasons they have their tap roots removed to allow the lateral and tertiary roots to develop and thicken; these roots if near the base of the trunk are the potential nebari.

Root damage – many plants will survive and recover from root damage providing the damage does not exceed 1/4 of the total root zone. Most of the important feeder roots of trees or shrubs are within the upper six inches of the soil and if damaged, uptake of water and nutrients is restricted reducing growth. In addition, root damage may take months or even years to progress, and it is during this period where problems begin which can cause symptoms of decline or death depending on the situation and how much damage occurred.

One of the biggest problems when root pruning bonsai is the lack of care taken, we have witnessed countless instances where the root ball is attacked with 2, 3, and 4 pronged instruments. The roots are basically ripped apart causing irreparable damage and as stated if more than 1/4 of the total root ball is damaged chances are that the tree’s health will diminish for some considerable time and this is where it is susceptible to attack from pests and disease.

Root pruning is an important factor in bonsai horticulture and should not be attempted half heartedly. At T.B. we have some large bonsai (Omani dai class) and these do take considerable time to re-pot. When teasing out the root ball a blunt single root hook is used that does not cause any damage. After which the roots hanging down and separated can be pruned accordingly with sharp shears nonetheless, others will use instruments that they prefer.

This brief discussion on germination and in particular the functionality of a plant’s root system may lead to a better understanding of its importance, more on root pruning can be found in articles 08 ‘Styling, wiring and pruning’ and 54 ‘Summer pruning’. Until next time, BW, Nik.

Article 82 – ‘Organic versus chemical’

Hi, welcome to Taiga Bonzai in this article we discuss the never ending problem of pest control that occurs on an annual basis that if not kept in check, will increase to unprecedented levels. In eradicating the unwanted two schools of thought are given, the ‘organic or chemical’ approach.

Introduction – there are countless species insects of which 10 million exist throughout the globe however, some entomologists say the number could be higher. Not all are a major problem, in fact many are predators helping to eradicate those whom cause devastation to plant life, these include Ladybugs Coccinellidae, Green Lacewings Chrysopidae, Honey Bees genus Apis, Praying Mantis family Mantidae, Spiders family Arachnida, Ground Beetles family Carabidae, Soldier Beetles family Cantharidae, Assassin Bugs family Reduviidae and Robber Flies Asilidae.

Eradicating the unwanted – arguably it is the most common of pests that are the problem, but much depends in what part of the world one resides as there will pest species endemic to your region. Here in the northern hemisphere pests include: Red spider mite Tetranychus urticae, Mealybugs Pseudococcidae, Aphid Aphidoidea, Scale Coccoidea and Sawfly Craesus septentrionalis all of which destroy plant tissue causing major problems and even death. Of course there are many other species to contend with some of which are immune to control, recent published articles ‘unseen enemies’ parts 1 to 4 gives more in depth information on this subject.

Finding a solution – according to the National Pesticide Information Centre (NPIC) there are different methods to eradicate pests and disease, “Fungicides are pesticides that kill or prevent the growth of fungi and their spores. They can be used to control fungi that damage plants, including rusts, mildews and blights.” “Fungicides work in a variety of ways, but most of them damage fungal cell membranes or interfere with energy production within fungal cells.”

Chemical approach– insecticides for eradicating pests are normally purchased in liquid form used in various spraying apparatus, they are poisons and can be classified in several ways on the basis of their chemistry, their toxicological action, or their mode of penetration. These chemicals not only kill the intended victims, but also other non-insect pests that are beneficial. The 4 categories are; Organic insecticides – Synthetic insecticides – Inorganic insecticides – Miscellaneous compounds.

The chemical Malathion

Banning the poisons – these chemicals regardless of category are detrimental to other plant life, to animals and human health. For example, Malathion manufactured by Dow Chemical is linked to developmental disorders in children and has been found by the World Health Organization (WHO) to be probably carcinogenic to humans. Conservation and public health groups sued the Trump administration and Environmental Protection Agency (EPA) chief Scott Pruitt, for failing to protect endangered wildlife and the environment from the dangerous pesticide.

Thus far the total ban on insecticides is 12 world-wide with another 27 under investigation, according to Nathan Donley in his ‘Environmental Health’ volume 18 Article number: 44 (2019) “The USA lags behind other nations in banning Paraquat, one of the most acutely lethal pesticides still in use today.” Not a ‘gold medal’ winning performance by any standard – so what is the problem, why are nations so indecisive in taking action against chemical usage?

Arguably it is attributed to 4 criteria. (a) Not all insecticides are effective because much depends on the species and many we know of are immune. (b) Nations are concerned with their own pest problems and will avoid using chemicals that have not been tried and tested. (c) Import/export using insecticides on crops is dangerous to human health, hence people are reluctant to purchase food if they are unsure of its origin. (d) The financial aspect – according to the GlobaL Insecticide Market it was valued at USD 12.11 million in 2020 and is projected to increase to USD 17.70 million by 2026. This market has high employment numbers that will be jeopardised if profits are diminished.

Organic approach – a solution called insecticidal soap which has been in use for eons is believed to cause damage to an insect’s cellular structure, the soap is sprayed on to an infected crop and the pest is coated and eradicated forthwith. It is contended that the effectiveness of insecticidal soap involve a physical effect on the insect for example. Damaged membranes, dissolving the insect’s wax coating leading to death by dehydration, disruption of the insect’s hormones, interference with the insect’s ability to breath and negative effect on the insect’s metabolism.

Horticultural soap

Insecticidal soaps are made from potassium salts of fatty acids (potassium laurate) which have a devastating effect on the insects, but not the plants on which the insects are devouring. Insecticidal soaps are most effective on soft-bodied insects including aphids, greenfly, whitefly, blackfly, mealybugs and scale insects. They can be effective against larger insects such as sawfly and other caterpillars. Predator insects such as ladybugs, honey bees, praying mantis, beetles, assassin bugs and wasps are not usually affected by insecticidal soaps and this makes them useful especially in confined spaces, greenhouses and polytunnels where said insects are welcomed.

Nonetheless, some plant species are adversely affected by spraying insecticidal soap, hence it is prudent to do a test before attempting a full-scale application. Insecticidal soap is permitted under most organic regimes, it is safe where children, birds and domestic animals are concerned. Insecticidal soap is a relatively simple product that works on contact and acts on the physiology of insects to eradicate them. Insecticidal soaps have several advantages over pesticides, they are non-toxic, leave no unwanted residue and are less expensive than chemical insecticide solutions. Insecticidal soaps can be purchased from appropriate outlets or made at home, here is a simple recipe example.

Step 1. – fill a 1 gallon (3.785 L) container with either rain water or distilled, not tap water as it contains alkaline properties making it hard thus reducing the effectiveness, make sure to leave room a gap at the neck of the container for other ingredients.

Step 2. – add 2-½ tablespoons of mild unscented liquid soap and 2-½ tablespoons of oil either vegetable, peanut, coconut or olive it matters not which. Both the liquid soap and the oil act as surfactants to prevent the solution from quickly running off the plant’s leaves when sprayed. The longer the solution remains on the plant’s foliage, the better the chance of dispatching the insects. Do not increase the ratio of soap or oil, it must be a very mild solution in order to protect the plants.

Step 3. – replace the container cap or lid and shake the solution to disperse the ingredients evenly, then pour the required amount into a spray bottle shake again then begin spraying the infected plant. It is advisable to re-shake the container prior to re-filling the spray bottle as this remixes the solution. The above horticultural soap recipe is one approach, there are many others using additional ingredients including vinegar for example, hence it might be prudent to research the subject further for piece of mind.

Although insecticidal soaps are safe for many plants, vegetables and fruit trees, a few are sensitive to the solution resulting in leaf damage, these include sweet pea, begonia, impatiens, azalea and rhododendron. If unsure whether it is safe to use insecticidal soap err on the side of caution and do a sensitivity test first on 2 to 3 leaves of the plant. If there are no ill effects after 24 hours and treated leaves look as healthy as before then it is safe to continue spraying, if the results are the opposite do not treat the plant further.

The fight continues – we wrote this article in September 2021 with the intention of posting it, but it was withheld due to Covid 19 and the restrictions imposed, although certain mandatory commitments still required our attention. In addition, there were reports of bans on various products including food and increases in different government’s legislation further exacerbating the problems at the time.

As scientific researchers we wanted to find out the reason behind this phenomenon, hence we wrote a series of articles called ‘unseen enemies’ 62 to 66 that gave rise to a lengthy discussion on how pest and disease was spreading throughout the globe. A huge problem caused by mankind’s idiosyncratic actions over the eons. Pests and disease that were once endemic to particular regions have spread world-wide destroying forestry and horticulture on an unprecedented scale. This article ‘organic versus chemical’ is a way of dealing with common pest and disease problems that we know of, but it is not an effective solution on all invading species. Until next time, BW, Nik.