Further Thoughts on Turface

A couple years back I wrote a post which became one of most viewed posts I’ve ever written. It was about Turface and similar soil ingredients like Oil-Dri and Profile, and my skepticism about their qualities as a bonsai soil ingredient, following 30 years of experience with many different soil types. The post was meant to call into question the belief that Turface is the best soil ingredient. I don’t believe it is, having witnessed its performance for years, but that doesn’t mean you can’t grow a tree in it, or that it may be one of the few options in your area due to availability issues.

In rough strokes, there have been three main evolutions in our soil usage in North America. Earliest was the potting soil/sharp sand period, decades ago. Then came the Turface era, which was definitely an improvement on the earlier mixes. Then came the volcanic mixes preferred by the Japanese, the pumice, lava, and akadama soils, one of which, akadama, needs to be imported.

While the debate hinges on what works better, it is compounded by issues of availability and price. On the east coast akadama is very expensive, needing to travel farther from its source in Japan. Pumice is rarely available in the east, and is only spottily available in the middle states.

Certainly if you hate the very idea of importing soil components, like akadama—an understandable position, I don’t like it either—try pumice if you can find it. It’s from our mountains here in the western US, and locally is dirt cheap, 17 cents a gallon in some places, and works well as a base soil ingredient to which other things may be added (such as akadama and lava if you have a bonsai, or composted bark/steer if you have young stock.) Naturally, trucking pumice east is going to be expensive.

If you prefer to use Turface, definitely sift out the small stuff. You may find that deciduous trees are happier in it than pines, as it tends to hold a lot of moisture and the particles are not very large.  Also, you may need to water very frequently in order to prevent the hydrophobic qualities of the fired clay product that happens on its surface on dry, windy days. These comments are for 100% Turface; adding other things may mitigate these issues.

I think we’re looking for a base ingredient that can be used all over North America (apologies to those readers in other continents/islands, although there may be a similar discussion worth having in your area.) I think pumice is a much better base ingredient than Turface, with much more dependable horticultural properties. If that is impossible to find in your area, I have no argument.

Some have had success using Turface. You will be able to find people who have had good luck with it, their trees are strong and healthy with good root systems. And then there are a lot people who can’t seem to replicate those successes.

At the end of the day, it’s really amazing how many different types of soils one can use to grow plants in. I’ve seen people use something close to concrete, a clayey thing that was terrifying to behold, and have a margin of success with it. In some places in China they use essentially pond muck. We can learn to use almost anything. But I really don’t think that’s the question, or at least, it’s not a question I’m interested in. I’m curious what is the best thing I can recommend to the broadest range of people wanting to grow bonsai, the broadest set of abilities and goals, and in answering that, I repeatedly come back to the volcanic soils the Japanese have used for a long time, and continue to use.

If volcanic soils are unavailable, keep experimenting, keep exploring, but don’t settle for Turface (and Oil-dri.) It’s not impossible to grow a tree in it, that’s not the point, it’s just not ideal.

Incidentally, James Hooper has just had a delivery on the east coast of some of our western pumice, and offered to have his name and number put here for anyone seeking it: 617-823-7154, and Jonas Dupuich of the blog Bonsai Tonight sells and ships bags of both akadama and pumice.

(Finally, a disclaimer: It won’t matter much what soil we use if we’re using questionable horticultural practices like barerooting old trees each time we repot. Please don’t do this. Without leaving a solid mass of soil on the roots we won’t manage to create the dense, stable, dependable root systems that we should see in our pots each time we take them out. This disclaimer could go on for pages on multiple subjects. But soil choice is a primary decision.)

Further reading…or pre-reading, actually, as this was the first post on Turface:

http://crataegus.com/2013/11/24/life-without-turface/

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43 Comments

  1. bonsai eejit says:

    Reblogged this on Bonsai Eejit.

  2. Gerald says:

    Over the last 30 odd years I’ve used most anything you can think of for bonsai soil. The only thing I always calculate in my mix is air content. Looking for 30 to 35 %. Beyond that, I think it comes down to controlling health and growth with fertilizer.

  3. Rick Johnstone says:

    Here in Port Charlotte, Florida we use lava rock as the base component. We add turface and ground pine bark according to the species we’ll be potting.
    We have a lot of newcomers and this is a basic blend they can start with and is easy to get and not an expensive blend. We’ve developed some nice roots with this base mixture.
    Love your blog, keep up the good work.
    Rick J. In Florida

    • crataegus says:

      It’s likely to be a good mix. Since you already have the water holding capacity of the bark, however, you really don’t need the Turface. Also be sure the bark has been composted a good while. ‘Fresh’ bark is a fertilizer drain, lots of nitrogen will be lost decomposing it.

  4. paul3636 says:

    When working with nursery stock for the 1st time do you recommend bare rooting all trees and switching to a bonsai soil? Do you have any experience with perlite?

    • crataegus says:

      Like most things in bonsai, it depends…if you have a five year old deciduous tree, barerooting is an option. Older trees and all conifers I would not advise barerooting, but rather teasing away the soil on one half of the rootball, essentially barerooting part of the tree, to the trunk. Then the next time you repot, in two years or so, do the same on the other side, and leave the work you did two years before untouched. That way in two repottings you’ve got an entirely new soil throughout with no danger to the tree.

  5. Brian says:

    Hi Michael
    A bit off topic but we have had some bonsai theft in the area over the past year and besides the odvious is there a chip or something you can put into your tree that would be traceable, and economical.

  6. Leo Schordje says:

    Michael, could you discuss Perlite? In the Midwest and East of USA it is widely available, and less expensive than imported media. It seems to be a great substitute for pumice if pumice is not available.

    • crataegus says:

      Perlite is amazing stuff. You can grow a ton of roots in it. The only real problem with it is that it’s so light it might float away. Some pumice has this problem too, but it’s heavier than perlite. Still, it’s an option if you can find a way to weigh the perlite down a bit. Mix with some lava maybe, or bark.

      Perlite is essentially the industrial version of pumice. Perlite is exploded sand (as I understand it), and that’s pretty close to what pumice is, volcanic glass that has a lot of spaces in it created by gas. A geologist could chime in here and make more sense of this I’m sure. But perlite is somewhat similar to pumice.

      One of the advantages to perlite is the same as the advantage with pumice, they are both water holding and drainage particles. Perlite holds a LOT of moisture. It’s very light when dry, and then gets very heavy when wet. One could say the same for Turface and other fired clay particles, water holding and drainage, but they don’t seem to create the same root systems.

      The horticultural perlite one can get has many different sizes to it that you can sift.

  7. paul3636 says:

    Another note on perlite
    I am 80 years old and some of my bonsai are heavy.
    My arm and shoulder still hurt from carrying some of them last fall.

    • crataegus says:

      Totally understandable. Pots are heavy enough. You might try perlite as a base soil ingredient mixed with something to keep it from floating away, or at least in the top 1/2 inch or so.

  8. Bob Kazarian says:

    Michael, excellent as always. I so enjoy your info and look forward to it every week. Please continue your efforts.

  9. Jim Sullivan says:

    Michael, You seem to have backed away a bit from your prior adamant opposition to Turface. If I recall correctly, a former curator of the bonsai collection at the US National Arboretum too was opposed to its use in bonsai, but because of probable toxicity to plants. Is there any scientific evidence of that toxicity? I appreciate your artistic, technical, and scientific approach to bonsai.

    • crataegus says:

      No, my own position is that Turface is a second-ranking soil mix particle, that is tricky enough to use that it can be the cause of great problems for people. Some will want to use it, and for those I try to offer my thoughts on how to use it best. But my earlier comments stand.

      I have no idea of toxicity, never heard of that.
      Also (although I appreciate the thought) I don’t claim to be scientific in my commentary. My comments are based on experience and witnessing results from a wide array of people, lifestyle, training goals, soils, climates, countries… My father was a scientist, and I grew up with them. I know enough to know I’m not the one to convince those expecting proof, although my hat is off to them because I’d like that proof from a disinterested party who has the scientific toolbox to do it. So far most of us doing experiments have something to prove. And so far I hope I’ve vetted myself with being someone who’s seen more results than most. That’s about it.

  10. carterbeall says:

    What is your opinion on expanded clay aggregates? Because they are fired and heated further until they expand, they appear to have a similar porous structure to lava and pumice but don’t seem to repel water like Turface. I don’t think it has any CEC either. I am curious what you think because a nursery owner recommended that I pot a Juniperus rigida in it straight.

  11. For awhile I have used a pumice, a paticular fired clay (an oil dri like turface but fired hotter and is harder). I was/am having good results with healthy trees. But the bummer is the pumice supplier closed and now the only option of getting pumice is as much or more of imported akadama. Switched the pumice out with crushed decomposed granite and seem to have basically similar results. Would love to get back to pumice but unfortunately didn’t win the lottery jackpot. Lol. Thanks for the articles and advice. Always look forward to your posts.

  12. Per says:

    Have you had any experience with moler as a substrate?

  13. Gumper says:

    Where i live we have a product called Zeolite. Has anybody heard of it and is it the same as turface?

  14. Kathleen e wigg says:

    I’ve read your material on why not to use Turface if there are other options. For succulents it appeared you were only using using two components Of which Turface was one. If it’s used in a 3 part mix as in “Bonsai Jacks ” best succulent mix it may be a different outcome. You can look up his site and Se what he says about his mix. Please comment back. I’m investigating all products before deciding what to source for my potted succulents. Plus I grow s lot of epiphyllum in hanging pits/ baskets. Kathi. Australia..

  15. Gary says:

    Well definitely living in Knoxville and on a budget pumice is hard to come by and $$-wise prohibitively problematic especially if one is working with a number of trees, coniferous and deciduous. Anyone tried to work with a Turface + Pumice/Volcanic mix that is amicable to a good root production yet is still partially constituted of Turface? Any suggestions would be appreciated.

  16. paul3636 says:

    17 cents a gallon????????????
    The cheapest that can be find is on ‘Amazon’ At $5.40 per gallon for 5 gallon pail, $27.00 delivered. I buy one a year and mix with what ever is cheap, usually perilite, chicken grit, oil dry, or pine bark. At present am experimenting with ‘Espoma’s soil perfect’ which is a crushed fired clay they claim holds water and air.

  17. joshmilonas says:

    Thanks for your thoughts on Turface Michael. I live in Las Vegas and it has been hard to get anything but Turface locally at a reasonable price. I recently tried to find Pumice after reading your article and was unsuccessful. I did however find 1/8″ black lava and after a sieve its perfect. I was wondering what your thoughts are on Pumice vs lava? Equal value, with the exception of weight? Also, I water daily in the growing season and thats no problem. However I don’t like to water more then once if possible. I have been using about 20% Peat moss in my mix, since it can reach 110F daily in the summer, that seams to work well. I was going to try 20% bark chips, but feel this may dry out too quickly. What would you recommend? Thanks!

    • crataegus says:

      Hi- long question with lots of good thoughts. Lava (scoria) and pumice are in many ways alike. Some lava is very light, and has better gas exchange in the mix, much like pumice. So if you have the chance, get the lightest lava you can. Also, I’d add some sphagnum moss to your mix, also sold as orchid moss, not peat moss. (Peat being decomposed sphagnum.) Try about 10-15% of it. Sphagnum will last a long time, won’t decompose, and hydrates immediately when bone dry. Peat is water repellant when dry, and very fine. If you try bark chips, that’s ok, just be sure it is composted bark. Non composted bark is going to eat up a lot of nitrogen.

  18. pone1 says:

    How does pumice compare to red lava rock? I hate the white color of pumice, so this is purely about finding a similar volcanic rock that has a brown or red color tone.

    What is it that makes akadama such a good planting medium? It crushes easily so won’t it quickly become fines in the soil after a few years?

    • crataegus says:

      Many of the red lava sources are nearly pumice, being very light and all. Black as well. Those are certainly possible for your mixes. Some are heavier and have a very different internal structure.

  19. Jez Jax says:

    I’ve really enjoyed your blogs on soil and pinching junipers and intend to read more. I just recently started following Ryan Neil of Bonsai Mirai. I have to laugh because I’ve only watched two of his presentations; in the first one he said, DO NOT PINCH JUNIPERS and in the second one he said, DO NOT USE TURFACE. His reason for not recommending Turface is that it absorbs water but doesn’t release it back to the plant. So retaining water is important but so is providing the plant access to that water. He’s kind of on a mission to find a substitute for Akadama. As part of that goal, he does seem very interested in Diatomaceous Earth and will be experimenting with that. He also has been testing a product that unfortunately is only available in Canada called Chabusai. I may have this wrong because I can’t find anything on the internet. I think it’s similar to Zeolite, which I’ve only heard of. I’ve also heard about a product called Calidama made from an indigenous California clay by a man named Glenn Van Winkle near Fresno. He makes it but doesn’t really distribute it. People have to go to him to collect it and then they sell it or he may take some to a bonsai swap meet. There’s also a lot of chatter online about Kitty Litter (Diatomaceous Earth, Diatomite, especially in UK). I’ve heard of using Haydite which is an expanded shale. I’m currently using pumice, a terra cotta-like decorative stone, sphagnum moss, a little vermiculite, aquarium stones and some Akadama I had left over. I don’t have many trees and they are small so I buy small quantities. I am thinking of finding some decomposed granite. I was going to add some small sized orchid bark (fir bark) but you said not if it’s not decomposed or composted. I’m planning to start looking for some lava. My question is what do you think about Diatomaceous Earth (granular) in the form of Kitty Litter, and do you know anything about Calidama, Haydite, Chabusai, Zeolite? Interestingly, the volcanic soil in Oregon and maybe Washington, seems very similar to Akadama.

    • crataegus says:

      It’s an important conversation. The urge to get away from akadama is a good one; the doors on importing it could shut at any time. It works well, but we could use a substitute. Ryan is correct about Turface. It’s funny stuff, and does exactly what it was designed to do: soak up water. I think experimenting with Diatomaceous earth is a great idea. I have an apprentice from Tasmania who says that’s mostly what they use down there, and that there are definitely different grades of it. Some, in my experience, dissolves on contact with water. Other mines are getting some that stay hard for years. I’d try to find larger soil sizes than what is available for kitty litter—and kitty litter is generally of the type that dissolves with water. Experiment!
      The other soils I know of, like Calidama, but I’ve not used it. Haydite I would avoid. It does not have very good internal properties like lava and pumice do, and the root structures that develop in Haydite soils prove that. Again, compared with these other soils.
      I’ve said this several times, but one can grow something in nearly anything, that’s not really the conversation. What works best in comparison to others is, and we’re all trying to figure that out.

  20. Robert Grealish says:

    Hi Michael. I agree with the hydrophobic aspect of current turface, and I won’t use it. I’ve been doing this for 35 years, and I used to get large turface, with a particle size of about 1/4″-3/8″. I used it mixed with various things for several years with good results. I happened to have a couple 25 year old bags, and I recently (4 years ago) tried it mixed with pumice 50/50 for a large cascade red pine. It worked beautifully. For some reason they stopped making the large size. Still looking for a substitute for akadama.

    • crataegus says:

      Yes, if you sift out the small stuff, and then mix it with something else, Turface does improve. It’s by itself that we tend to see the most problems.

  21. paul3636 says:

    A mix I have had good results with on pines is 50/50 Perlite and soil perfect.

  22. Pre-nubie says:

    Hello!
    What a wonderful discussion. I’m not even a newbie yet, but researching soil first before I begin.

    Being in a humid and rainy temperate area (hardiness zone 7-8), and not the least bit interested in housing bonsai inside, what would be a good mix to start with?

    I don’t mind watering, but am concerned with rot, and also flushing nutrients.

    Thanks for any helpful, experienced advice!

    • crataegus says:

      Hello—yes, soils are a long conversation with many answers. But, a popular mix for conifers is 1 part pumice, 1 part lava (scoria), and 1 part akadama. For deciduous trees, 1 part akadama, 1 part pumice.

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