Thursday, June 17, 2010

Feeding, Substrate and Watering - English

Feeding, Substrate and Watering
Methods of Walter Pall (edited by Victrinia Ridgeway)

I was asked to write a paragraph on the 'feeding of conifers'. So I sat down and came up with this. But the question, “How do you feed conifers?” when given a short answer, can lead to serious misunderstandings and to fatalities.

Substrate, watering and feeding cannot be seen as separate. Each is connected to the other and so it becomes quite complex. Be it a deciduous tree, conifer, young, old, recently potted, or even collected, there are so many variables inside a bonsai garden. Can there be a clear answer?

Well, yes. But one has to read quite carefully and then do EVERYTHING. It is not feasible to pick one that you like and ignore the others. You cannot feed according to my method and don't care what substrate you have or what your watering regime is.

First, I set aside everything that has been written in most bonsai literature about the subject. As technology grants us access to new and more effective methods and products, the way we care for our trees has progressed beyond the boundaries of tradition. It has been a new and modern world for some time, but many have not realized this. Even if some measure of success is achieved with the old methods it can be dangerous if used with modern substrates and practices, or even deadly.

Substrates: Good substrate material must: be of equal particle size, have the ability to absorb water and release it back, have no fine particle organic material, must not decompose easily, be as lightweight as possible when dry, preferably inexpensive and should have an aesthetically pleasing appearance. This would then be: lava, pumice, baked loam, Turface, zeolite, Chabasai (a type of zeolite), coconut pieces, bark pieces, Styrofoam pieces (no joke) and a few more which you can find yourself if you have understood the principles. Please note: Some of these materials may not be available in your area.

Normal akadama is questionable as a good substrate as it inevitably decomposes, especially when exposed to winter frost. It can become deadly loam in the pot, choking the flow of water and air into the soil. This is especially true for trees which are only rarely repotted, like collected conifers and old bonsai in general.

Substrates which are not useful: soil, compost, stones, sand etc. Trees grow in sand and flower soil, of course, but it is not an optimal growing medium for health in bonsai culture.
All substrates can be mixed according to your liking and it makes almost no difference. They can also be recycled and used again, but make certain to sift and clean any recycled materials as needed.

There is no such thing as an 'ideal bonsai substrate'. There are in fact thousands of ideal substrates. I believe that IT DOES NOT MATTER WHAT YOU USE AND IN WHAT MIXTURE as long as it is a modern substrate.

Since there is no soil in modern substrates there is very little alive in them. They dry out easily and one must water several times a day when it is hot, especially if you have used pure inorganics. Therefore I add rough peat in addition to the previously mentioned substrates. This is the kind of peat that is harvested in bogs and comes in its natural coarse form. Make certain not to use fine particle peat/sphagnum moss, even if the package says “dust free” as the particles will be too small. If you cannot find the correct type of peat, use small bark bits without dust particles, or cut coconut fibers. These organic components should comprise 15-20 % of the overall volume, a bit less with conifers, olives and such, and a bit more with small trees and azaleas.

These organic materials are good for keeping humidity higher in the substrate and for supporting the colonization of beneficial microbial life in the soil composition. Research also seems to indicate that peat moss has plant hormones which are good for trees. These are organic materials which would normally have no business being in a bonsai substrate, but the ones mentioned take five years to decompose. You have to consider this when planning your repotting schedules. The organic material should also be sieved out of any substrate that is being recycled.

Watering: I have a watering schedule that runs from the end of March to middle of October EVERY day. This is regardless of whether the trees appear to be dry or not. Only when it rains heavily will I refrain from watering the trees. When it is hot, or there is strong wind, or a combination of the two, I water two or even three times in a day. Very small trees must be watered twice a day. ALL trees are watered the same. Individual watering habits are not needed when all of your trees are in a consistent well draining substrate. There is also no need to carefully train a friend how to water your trees when you are away. Any person can water the trees; everything must only be watered thoroughly. It also does not matter what type of water is used. Tap water is very usable for all plants, even if it is hard water. I have some of the hardest water in Europe in my garden (23° DH). I use this water for everything, including azaleas. I water with a garden hose, full speed. I do not water individual trees, but areas, just like you might water your garden with a sprinkler system.

When you water this way, water aggressively. This means everything becomes very wet, the whole tree from top to bottom. The water must run out of the draining holes. It is very good for the trees if the crown gets wet every day.

With modern substrates over-watering is almost impossible. You can water for hours and all of the excess will just run through the pot if the correct substrate is used. It is very easy to under-water though. Many bonsai die because they are sitting in modern substrate but are watered according to the old methods - under-watered in fact.

Feeding: With modern substrates and aggressive watering, feeding is no secret anymore. ANY fertilizer that is offered for ordinary plants can be used, whether organic or chemical. Fertilizers should have LOTS of nitrogen. Only with nitrogen plants can grow.

I use mainly liquid fertilizer that I get from our cheapest general discount market. In America it would be Walmart. Use general fertilizer that is noted as being good for all plants. In addition I buy a few dozen boxes of granular fertilizers which contain chemical and some organic ingredients. Two times a year, in the beginning of May and in the end of August, I throw a handful of dried chicken manure at the trees. I buy this in large bags, which is very inexpensive. That's it. For ALL of my trees including the world famous ones I use the same fertilizer.

How much? WAY MORE THAN YOU THINK! I feed from 20 to 60 times more than the average bonsai grower. From the beginning of April to the middle of October, every ten days everything is fed with liquid fertilizer, using three to four times the suggested dose. All trees are fed equally, whether deciduous, conifers, small, large, repotted, collected or not. This is a span of about 200 days when the trees are being fed. Since the trees are fed three times the normal dose on twenty days in that time, it makes for 60 doses of fertilizer in the growing season. The average bonsai grower feeds maybe three or five times at half the normal dose because 'bonsai trees should not grow'. If you then add two times a year of chicken manure being given to the trees, you can then understand why this schedule is 20 to 60 times more than the average.

Asian fertilizer cakes are fine but superfluous in our culture. We don't eat steak with chop sticks and don't have to feed plants with cakes. But they don't hurt if you insist of using them; they are just unattractive to look at. Biogold was made to be used with modern substrates like akadama, and it works well. If you give it to me I will break it into very small particles which I then throw all over the substrate surface of the trees. After one watering it becomes invisible.

Too much salt in the substrate is almost impossible if one waters aggressively every day. Even azaleas don't mind my treatment. They thrive very well with very hard water, ordinary baked loam and peat as the substrate and aggressive feeding like all the rest of the trees.
About ten years ago 'super feeding' was proclaimed and a while later forgotten. It did not produce the expected results and many trees suffered and even died. What I do sounds similar. Well, it is similar, only that I insist on aggressive watering in parallel to aggressive feeding and the use of modern substrates. I also don't make the ingredients of fertilizing trees into a science. I tell you to buy whatever is on sale in the garden center or agricultural supply store.

This feeding scheme is for trees in development. Remember that 99.8 % of all bonsai are 'in development'. If you happen to have one that should really not develop anymore you slow down its feeding schedule considerably. You let it starve on purpose. Then it will get smaller, and fewer, leaves and needles. It will look good for shows, but your tree will go downhill if you continue to do this for too long. After a few years you have to feed it aggressively again to let it recover.

Summary: Do all three or nothing! You have no choice here. To just pick one method and refuse the others will end in disaster. Those who do 'super feeding' using old-fashioned soil, and insufficient watering will kill trees. Those who use modern substrates, aggressive watering and fertilizes like the old days will have very weak and, in the end, dead trees. That's all there is to it.

So the question, “How do you feed conifers?” Gets the answer, “Like all other trees, but you have to know the whole story.”

I know that many will not believe this. ‘He who heals is right’, is a saying in human medicine. In gardening 'he who has the healthiest trees in the long run' is right. Come to see my garden or look at my gallery, they speak for themselves.

All this was not discovered or invented by me. I only learned from professional modern gardeners. They have done this for decades with great success. I have adapted modern horticulture to bonsai. Only in the bonsai world does this seem revolutionary.

Walter Pall


Jerry said...

Concise and to the point. This article will see a LOT of traffic.

Anonymous said...

that is very interesting to read.

Walter, 1 question now pops into my mind... do you have the experience that this treatment is also or less correct for smaller trees? I your experience, is it necessary to limit the feeding somehow if you consider pot (container) size? Many of your trees are rather big in rather big pots. Would aggressive feeding not be potentially more risky in smaller pots where there is more chance of raising the salt level and level of chemical particals to rapidly? Or do you simply compensate this also with aggressive watering?

Walter Pall said...

I have one of the largest collections of small trees, about 200 pieces. And I do exactly what I describe with them too. With very good results.

Ravi Kiran said...

Dear Walter a very thought provoking article indeed. I not only appreciate what you have said in the article but also am happy to get the larger picture of what you are saying/doing.

In India where I belong, being a proper tropical climate we need substrates which have relatively higher water retaining capacity. I guess you have also touched upon this when you say add some organic material like peat moss etc.

The other challenge for us here in India is that most of the modern substrate materials you have mentioned are not easily available. I was hoping sand would do the job but I was a little disappointed to see it in your list of "not suitable materials".

Overall a very ground breaking article and nice to see a sneak preview of your yet to be published book(s) :)


Matt Williams said...

Dear Walter,

Inspired by your regime (and that of others who use similar methods both in bonsai and other types of horticulture) I have been using a similar system for three years. I substitute an organic peleted fertiliser (slow release compound fertiliser with an analysis of N.6% - P.5% - K.7%. With added trace elements. Iron, Manganese, Zinc, Copper, Boron, Molybdenum) applyed from begining to end of the growing season (about 8 monthly applications).
So far, so good... vigorous growth and good disease resistance with no signs of any deficiencies! I use a baked danish moller clay cat litter with added coconut fibre as a substrate.
A friend who uses a blended organic soil to grow bonsai was amazed with the speed that my trees develop!


João Santos said...

Hi Walter,

One question pops up my mind to and for some time that I intend to ask you:

For some time I've read some older posts of this scheme you use but I've seen some pictures of you repoting (ex: the Huge Maple) and I see many "organic" soil instead of chabasai or baked loam (that I use) or other inorganic soil... Is it because the tree is already "done"?

And the question is: when I use smal pots for small (or younger) trees, can I use 100% of this? in full sun? or shoul I use a layer of organic on top to prevent it from drying?

Anonymous said...

Dear Walter

Why do you use inorganic fertilizer? Why don´t you use only organic fertilizer?

Anonymous said...

Hi Walter,

Great article!

Just one question: in the case of yamadori material - lets say yamadori pines with the pot volume consisting of 1/2 or maybe 2/3 of the original mountain soil - do you apply the exact same strategy as described in the article or do you adjust a little??

Ken Krogholm (Denmark)

Nik Rozman said...

Wow! That is a very inspiring article you wrote Walter. I can say it's all true what you wrote, since I use a simmilar methood.
Just super!


Anonymous said...

Hi Walter
Great to see all this advice in one concise article.
It seems the opportune time to ask a question I have had since reading an old article of yours in Bonsai Today #70.
In this article you state that hornbeams are salt intolerant and if you have a siol mix that needs watering often you should use rain water with them.
This was 10 years ago and although it seemed against what I have read from you recently it seemed to make alot of sense to me as I recently concluded that my leaf margin burn on hornbeams was from salt toxicity. I get edge leaf margin burn on the mature leaves while the new growth is undamaged. I believe I am using a modern mix but realise the year I had almost no margin burn was when I used a very weak fertiliser schedule!
I was planning on following the soil mix advice you gave in that article which would be a more water retentive mix than I usually use but now I am unsure?
I even installed a rain water tank so I have fresh water!
Thanks for any help

Anonymous said...

Dear Walter

This sounds very interesting.
Why do you also use inorganic fertiliser, and do you also apply this method to just now collected yamadori?
Isn´t the salt a problem for just collected yamadori?

Jan Zatko said...

Yes, as i can say, it really works, i do this, i have heard (read) about this method 3-4 years ago, and since i take care about my trees by this way.
by the way: a have noticed in your story, you do not recommend using of the sand, i am quite surprised. sometimes, i´m using kiryu, which is river sand (gravel, very small stones, it depends what is a fraction of kyriu, small, medium, large), and i think, it is very similar to zeolit, for example.

Al Polito said...

In the Pacific Northwest area of the United States, we have found that a mixture of akadama and pumice, or akadama, pumice, and lava cinder, screened uniformly, yields great results. I think we repot our trees frequently enough so that the akadama doesn't break down to the point of harmfulness. I'd love to try the WP method myself, but as a working professional, I need the akadama in the soil to retain the moisture that it does. One trick we employ here to retain moisture is to get commercial orchid moss, grate it, mix it with grated moss, and sprinkle it on the surface of the pot before initial watering. The mixture bonds to the soil surface and provides the "seedbed" for the moss to grow in.

Certainly Walter's trees look great and it's obvious his techniques work well.

Dallas from Utah said...

Great article Walter. I am the president of our bonsai club and was wondering if it would be OK to share this article with our club?

João Santos said...

Strangely I got anonymous... don't know why...

Walter Pall said...

Utah President,

of course you can share this with your club.


we have to define what I mean by 'sand'. I mean little particles of solid stone.
So kiryu does NOT fall in this bracket but kiryu IS modern substrate like zeolit. Of course you can use it.


organic fertilizer only works when it is warm form middle of May until end of August. And it smells and it is ugly. So I use chemical mostly because it is clean and you don't see or smell it. In parallel I use organic twice a year.
Did I not say that use ti for ALL trees, including recently collected yamadori.
Did I not say that you HAVE to water very aggressively to wash out salt?


don't listen to my crap from old days. I have learned and experimented a lot in the meanwhile and I use my method with hornbeams with GREAT results. The key is aggressive watering that will wash out the excessive salt.


the situation that you describe is a bit dangerous, yes. If you have 2/3 of original soil and only 1/3 modern substrate you must be careful.


what you see is NOT mainly organic. It is modern substrate with black peat.
With small trees in small pots you MUST add peat (sphagnum) or coconut fibers - 30 to 40 %. Otherwise the substrate will dry too soon and you have to water three or more times a day.

Anonymous said...

Thank you Walter for the information.

I cannot locate chicken fertilizer. Is there any reason not to use sheep or cattle fertilizer or even mushroom compost?

I read that chicken fertilizer has a little more nitrogen than the others but not very much.

Would the other fertilizers be a good substitute?



Walter Pall said...

sure you can use other organic fertilizer. Cattle, sheep, horses, fish, guano etc. All must be dried for two years or so.

AJ said...


When you collect a conifer, do you attempt to remove all of the soil that the plant was growing in and replace with your mix? Here in Colorado, a lot of the conifers are growing in 100% organic pine needle peat. Often i will leave it alone and place the root mass in turface so the pine peat and roots are surrounded with inorganic.

your thoughts?


Walter Pall said...

I would try to loosen the organic ball a bit and then plant it to be surrounded by modern substrate pure without and more ingredients. After one or two years if the tree looks healthy I would take it out and try to remove very much of the original organic soil. A couple years later again.

Anonymous said...

When do you start fertilizing fresh collected trees,Sir.


Walter Pall said...

Did I not write that I treat ALL trees the same, whether collected repotted etc. It is IMPORTANT to feed collected trees RIGHT AWAY. I said it and you only have to read it. Forget your book wisdom.

Hans said...

Hi Mr Pall,

Nice written article. Thanks for sharing!! I still have a question about the agressive watering method where you state to water the whole tree from top to bottom, and that it is very good for the trees if the crown gets wet every day..

If I do this, I will get problems with fungal diseases. I think this is not only my problem, or a substrate or fertilizing method problem, but a problem for many people. It seems you have no problems with this? Or how do you deal with this? If you use products to prevent these fungal diseases, which products do you use? Or other tips to prevent this are most welcome!

Many thanks,


Walter Pall said...


I honestly believe that this is a bonsai myth. If this were true ALL trees in Central and Northern Europe wold have serious fungal diseases and ALL trees in the tropical part of the world as it rains all over the crown for days and weeks. It is ESSENTIAL for most conifers to get a moist crown in many locations where it rains little. Is is a fact that trees DO NOT get fungus from being watered over the crown more than they wold get anyway. It is a BONSAI MYTH. Trees get fungus because they have a weak immune system.


Nick Guzowski said...

Hi Walter,
Great article. I have been growing with traditional soil mix but will be switching over my plants ASAP.
One question.
How often do you feed in the non-growing season?
I am in Australia, and even in the non growing season I have privets and others that still grow, but not as much. For these trees, should I be using a less aggressive feeding method? Maybe spread out the feeding to once every 20 days?
And is feeding required in the non-growing season for dormant and deciduous trees?

Walter Pall said...


if trees still grow slowly feed less, but still every ten days or so.
Dormant trees should not be fed. They will also not be watered very much. If fed there will be build up of salt in the substrate which is dangerous.

Anonymous said...


I've been following your method here for about a year and this year was one of the best I've seen yet! Tree's that I was sure were dead, came back after re-potting.

I water thoroughly twice a day and all of my trees are looking great! My yamadori are even developing fat buds, their first year! I feel really excited at the rate that everything is growing, how green everything is, and how healthy everything seems.

Could you explain a little about watering in the winter? We rarely get huge amounts of snow (zone 7) but we get very cold and dry winds. Do you still water heavily in freezing conditions? Could you explain watering, and temperatures to start covering or sheltering trees in the winter? THANK YOU VERY MUCH FOR THIS RESOURCE!!!

Walter Pall said...

I do water in winter when temperatures have been above freezing for a couple of days. It is essential to water when you have strong and dry winds. I would try to protect your trees from wind in these conditions. I start to shelter trees in mmy area about beginning of November to end of November. Most trees are just set on the ground from the shelves and posts. Smaller and delicate trees go into a cold greenhouse. But uis will freeze in there still. Deciduos trees are stored close to the house to protect them form wind and sun.

Joey Carrapichano said...

Hi Walter,

I have one small question regarding this technique. When one has collected a tree, and there is still some of the old soil left on the roots, which obviously cannot be removed, then this feeding regime is certainly going to kill the tree, or not? How do you go about removing the old soil from trees that have been collected be it yamadori or garden or even a plant from a tree nursery? When do you start this kind of technique?

Thanks in advance.

Walter Pall said...


it is not necessarily going to kill the tree. But you have to be carful to not overwater. Well, you have to get rid of the original soil from the habitat as soon a spossible. You start a bit when collecting, two years later and four years later. Then the tree should be in pure substrate.


A.Polanco said...

Great info Walter!! Thanks for sharing! Is it ok with you if i share this with my club here in PR?

Walter Pall said...

Go ahead, share it with your club.

Michael said...

You said that when temperatures are above freezing for a few days in winter you water your trees. During those days, do you water every day or less often?

Walter Pall said...

Michael, in winter I would water once a week or so. It all depends. You have to watch carefully.

Steezeven said...

Thank you.

Darkhorse said...

Thank you for this fantastic information and also the videos! I have used both as invaluable resources for my article on modern substrates.

We have different materials available in Australia but of course all of your wisdom holds true.

Anonymous said...

would you consider 50% of hard type of akadama and 50% of bims (all equal particles) an adequate modern substrate?

kindest regards

Walter Pall said...

Sure, I would add 15 % rough peat or coconaut fibres or small bark particles.

Anonymous said...

regarding the 15% of bark particles, what about decomposed pine bark particles of equal size (sieved) that is the same as the size of akadama and bims? if yes, should I add it to mixture that is for all type of trees, also leave trees?

you say you water aggressively whole trees from the top to bottom. Also in summer, at noon when is very sunny and hot? I am bit concerned about leave trees, like in example Japanese maples.
Thank you for your wisdom and advice.

Walter Pall said...

Absolutely not DECOMPOSED bark. Not decomposed organic matter! Rough peat and coocunt fibres are very slow in decomposing.
Forget the burning of leaves on hot days. This is a gardener and bonsai myth.


Anonymous said...

ok, I understand. I have also access to fresh pine bark that are crashed into small pieces, roughly about the size of big akadama particles. is that ok? obviously they will start to decompose slowly in the bonsai pot, but is it slow enough?

Walter Pall said...

This sounds much better.

Anonymous said...

Dear Walter,
so if everything is done correctly, I can fertilize my bonsai every ten days with four times the amount of general fertilizer and all will be ok? I am asking because I am going to do it:) for those plants that will be in this kind of substrate and I will water like crazy. Just need from you reassurance and green light:)

Walter Pall said...

Well yes, this is waht I am saying. I have to repeat: You MUSt have very well draining modern substrate with no decomposing or decomposed organic matters, NO soil, You MUST water agresively, you must water throughly until everything is wet and the water runs out of the drainage holes. Well, then you can use four times the regular strenght. If you are in doubt start with using two times and see how your trees like it. And you only feed when the trees grow. In my area I feed nothing at the moment and start to feed at the beginning of April.

akhater said...

Hi Walter,

I'm trying to "invent" a modern substrate that I can find in my part of the world (Lebanon)

We have no baked loam or pumice or lava rocks...

all we have is

Perlite, pine bark, Styrofoam, aquarium rocks and expanded clay and peat moss

Would expended clay with just 10% of peat moss do the job ? (temperatures here are rather high in the summer)

your advise is highly appreciated.

Walter Pall said...

I think you shoud give it a try. It should work.

Anonymous said...

Walter, I'm using this method for a few weeks now. The baked loam is from a brand named Seramis and peat moss. However, it looks like if the substrate is wet all the time and my Fuji cherry and larch doesn't seem to like this way of working. The leaves of the cherry are turning brownish, like if they have root rot or something. I know that root root is impossible.. but still... Am I doing something wrong?

Walter Pall said...

This sounds like you have way to much peat moss. I did never recomend peat moss but rough peat, about 15 % of volume.

Anonymous said...

I meant rough peat. I still get the names mixed. So I'm only using a very small percentage of peat in my substrate, but everything goes wrong. I never had this problem when I had my trees in hard akadama. The site of Seramis says that I only need to water the trees once a month! And yes, it is baked loam. I've checked it over and over again. It looks very much like akadama, only the shape and color is different.

Walter Pall said...

This is a bit strange. Why don't you cut down on your watering for a couple of weeks and see what happens.

Anonymous said...

Perhaps tt's still my fault, as both trees still have their original rooth ball. Their soil is surrounded by the modern substrate. Yes, I'll cut down my watering and feeding. Can I still replace the soil? After all, we are near the end of april.

Walter Pall said...

If this is so then technically your trees are NOT sitting in modern substrate and must be watered with care.
Well, it should still be possible to take off most of the old soil and plant the trees really into modern substrate.

Anonymous said...

Well, i did repotted the trees in the seramis substrate. It was a little bit of a mess, but they are now fully IN substrate and not sitting on it. And yes, the fungus in which the larch is growing, was transplatended with it. Hopefully, everything will come around now. I could let some of the old soil behind, but I don't want to do a half ass job.

Anonymous said...

Hi Walter,

I just tried using these techniques for the first time (85% pumice, 15% rough peat). After repotting I soaked the tree thoroughly. However, an awful lot of the rough peat is seeping out of the drainage holes when I water. I'm worried that there won't be enough left.

Is this typical? Will this eventually stop once the substrate 'settles' into the pot?


Walter Pall said...


sounds like you are nto useing rough peat. Here it never flows away because it is rough and has large particles. If it is dust it is NOT usable.

akhater said...

Hi Walter, I am back for more advise

I couldn't find rough peat and the peat-moss I found is "dusty" I did use it on some of my "trees" not very good.

I am using very coarse expended clay (5 to 6mm) purely on some trees, with 5% peat moss on others I am testing obviously.

I have access to pine bark in 2 forms one of them is like fibers and the other is big chucks (3 or 4 cm) which one would you recommend as substitute to the rough peat ?


Walter Pall said...

I would take the fiber bark and hack it into small pieces with an ax or similar.

akhater said...

Thank you for your help and patience

Anonymous said...

Walter I see you insist on the period 10 days to 2 weeks why not weekly?

It is just easier to build a schedule when it is weekly :)

And if weekly is ok do you still recommend at least twice the amount ?


Walter Pall said...

I insist on nothing other than that you either do as I do exacly or find out yourself and don't blame me for severe losses. I insist on that period for me personally. The reason is simply that it takes me two hours of hard work to schlepp 50 or more full very large cans to the trees. Otherwise all trees are watered within 30 minutes with a thick garden hose.

If you have fewer trees and more time and strenght it would be even better to water daily. You will have to find out about the dosage yourself. It is way more thogh than you can imagain probably.

Walter Pall said...

See this article in Croatian:

Anonymous said...

Is it okay to use cocopeat instead of the rough peat? The only peat that there are selling here, is a kind of peat that is made of very small particles.

Walter Pall said...

Cocopeat is posssible.

Anonymous said...

I'd like to make a comment on this way of working. When I planted my elms in baked loam combining it with the feeding and watering, I noticed that all elms lost their leaves, but were growing again within two weeks. They all look very healthy now. Is it common that deciduous trees will lose leaves when they are planted in substrate for the first time?

Walter Pall said...

This is typical for Chinese elms. They react with leaf drop whenever something changes. Does not matter!

Anonymous said...

Is it possible to use substrate that's made for ponds, or does this holds to much moist?

Walter Pall said...

I don't know your substrate. It is importat to undertand what substrate is all about. then you can find many possiblities on your own.

Anonymous said...

That's the big question. I've read on many pages that's made of some sort of baked clay. Other pages are telling me that it's made of some kind of lava. At this moment, I'm using hard baked akadama, but I'm looking for a cheaper and better alternative. The brand name of the substrate is Velda.

Walter Pall said...

Baked clay and lava are both good.

Anonymous said...

Today I bought the pond substrate. The particle size looks right and the color to. I checked the bag and it does what substrate has to do: it absorbs water and gives it back to the tree slowly. Hopefully, it works for my small hornbeam project.

Marc said...

Walter, after a very good summer and with good growing trees thanks to your method, there is still something I would like to point out. After agressive feeding and watering, the top layer of my substrate is turning green! Is this common:

Anonymous said...

I have a question about substrate and watering. Now that it's autumn, the substrate still goes dry very fast. Yes, I added the peat. Despite I still have to water every day. Doens't it have any effect on the trees during their resting period?

Walter Pall said...

You have to think for yourself. Here in my garden in the past 15 years I only watered every two weeks in November. This year I have to water three times a week.

Anonymous said...

Thank you for the quick reply. Were I live, it was a warm spring with a cold en wet summer followed by a pretty hot autumn. Last week, it was still 17 Celcius here and now only 8. My hornbeam and larch have lost their leaves and needles, but my shohin elm is still completly green. I'm using very small lava subtstrate particles ( 1.5 - 2 mm ), but it's very difficult to know when the trees need their water in their resting period.

Anonymous said...

I've a question about feeding and winter/spring. My entire collection of shohin bonsai are staying in a greenhouse because of heavy frost. Now the trees are budding. Is it wise to start feeding?

Walter Pall said...

You can start to feed a little. When the foliage is out the full feeding program starts.

rps said...

As you are no doubt aware, this fine article has been activated again on the IBC web-site through recent comments --- which is where it was brought to my attention.
Based on discussion with local club members, various readings and some [limited] experience, i am already in line with your substrate and watering views --- having read your article and considered its logic and merit, i am now ready to embrace the third aspect of your "triumvirate": feeding.

one question to that end: if I'm reading correctly, you endorse a nitrogen heavy feeding regimen throughout the feeding season. I live in an area with long cruel winters and a hardiness rating of 3a. Will the new growth prompted by the N application at this time of year have time to harden off and, as importantly, develop terminal buds prior to the challenges of winter? Or is this even an issue?
Perhaps it's a simple matter of pruning back new growth to suitable buds as dormancy sets in?

Your guidance is appreciated.


Walter Pall said...

it seems to be a bonsai myth that trees grow in fall because of high nitrogen dose. This used to be gardeners wisdom. Modern research has shown that plants take whatever they need at a certain time and leave the rest. So you can throw as much nitrogen at trees as you like. They will only take what they need. It is true that they need less in fall. But so what, the rest is washed out.

I totally gave up to think for my trees. They do that much better than I can ever do this.

Cutting in late summer will induce new growth which possibly cannot harden enough and will die in Winter. I stop cutting broadleaved trees after August 10 in my climate. At the beginning of October I start cutting again because it is too cold for new growth to appear.

animesh said...

Dear Walter
Thanks for your article ,i have an question that when you repot, do u mix any fertilizer (such as bone meal,blood meal,hoop & horn ,neem cake Etc ) .Please give reply .

animesh Nandy

Walter Pall said...


no I never do this.

Anonymous said...

Hello Walter,

Thank you so much for your great insights! Your suggestions are very intuitive.

I have one question though. You suggest a heavy feeding regime and a heavy watering regime. But is it not the case that big parts of the fertilizer you feed to the tree are washed out again the next day during watering? So what I wonder is, are your reasons for doing so more economic in nature (makes it easier to manage a lot of trees) or do all trees effectively benefit from that much fertilizer? Or in other words, how much of the fertilizer you feed to your bonsais do they effectively use on average (if there is a way to know that)? Or maybe in yet other words, how did you come to choose this amount of fertilizer?

Thank you for your time and help!


Ann said...

Hello Walter,
I am interested in your comments on watering and feeding. So many experts talk about specific feeding with different feeds, differing watering times and quantities that I often feel that I'm not caring properly for my trees. Would it be possible for us to reproduce some of this article in our club magazine please - Hamilton Bonsai Club, Hamilton, New Zealand.
Kindest regards,
Ann Mudie, Hamilton Bonsai Club, New Zealand

Unknown said...

Hi Walter, thanks for your article. I Have been doing a similar regimen and every time I read an article with older techniques I always feel like a sinner. LOL I have a question about the median I have been using. I live in Las Vegas, so its very hot in summer 117F at times, but our growing season is 10 months. I use a median formula as follows.

1 part MVP Turface
1 part diatom
1 part builder rock
1 part bark (Non Decomposed)

All of it is sieved between 1/4" to 1/8".

I was wondering how you felt about that formula, and if there is anything I can do to improve.
Because it is so hot here, I felt 25% organic was needed.

Walter Pall said...

I would leave out the builder rock.
for conifers:
1 part turface, 1 part diadom, 1 part bark
for broadleaved trees, and conifers that want it moist
1 part turface, 1 part diatom 1.5 parts bark.
the rock does nothing other than fill volume. In your climate you absolutely need components that can hold water which the rock cannot.

jeremy said...

Hey Walter,

So when winter winds are strong, how can you tell? I guess I'm saying where do you draw the line between windy and very windy? Will the soil dry out?


Walter Pall said...

Oh well, Jeremy, it is allowed to use common sense.

Anonymous said...

Subjective.. There is not a single rule..appreciate it though.

Joe said...

Excellent article !

One question . Assuming i plant a tree in modern substrate that does not break down, and i have barerooted the tree so i won't have any soil. If it survives, and i want to repot after 2 years, will the modern substrate be compacted like soil or will it all fall apart when i lift the tree out of the pot ? Thanks

Walter Pall said...

Joe, it will fall apart and you can shake it out - even after twenty years.