The shale may affect water chemistry, so will check that first with this coarse cut…but also have to get a finer screen of it to know if it is good for the trees texture-wise. This cut could be used as coarse base layer for drainage, but not much more.
I bought these in 2018…but they must have been more like $70 then. You can buy them individually too. I would maybe just get a 1/4” and 1/8” set for $50 as those are the crucial sizes for bonsai soil.
Hi Don,
I use a shale product as the primary in my bonsai mix due to the highly humid climate I live in, coastal South Carolina. The product is called Permatill, it’s what is called expanded shale, heated to 2200 degrees. It has a good CEC, and has done well for me the last 2 seasons. Doesn’t break down at all, down side it is a bit heavy, and the size typically is on the larger size when sifted. Hard to get enough small material if you’re doing lots of smaller trees.
Hi SC Bonsai Grower. I’m a NC Bonsai grower. I picked up 1/2 bag of Permatill at a club auction. I looks like volcanic rock and I would think it would be a substitute for harder to find volcanic rock here in NC. I would think the bonsai community would be excited to try it and use it but, I really don’t see almost anyone talking about it and happy about it. I’m in zone 8 B outside of Raleigh. Any thoughts on this? Thanks - Joe
Hi, so on the subject of Permatill, I’m in coastal SC, moved here from PA in 2013, I only brought a few trees with me as many would not survive the transition, I struggled with them due to the heat and humidity, took me 3 seasons to figure out a mix that would keep them healthy.
So I use it on all my materials that go from development into bonsai training containers, makes watering easier since I have it automated.
I use Permatill in place of akadama, it has similar CEC rates, doesn’t seem to do as well at promoting very fine root structure as akadama due to structural differences, but it’s not bad, and it doesn’t ever break down and cause issues like akadama can. I actually have pines that have been in the same training pots for over 6 seasons, still drain great and trees grow very vigorous. Surface cleaning is all I do each season.
Biggest down side is the weight, and grading, it runs large for smaller trees.
Soil is such a contentious subject, I rarely bring it up, except to local hobbiest that are struggling with their trees. However most of the hobbiest in my area have very young trees,
My mid is as follows
30% Permatill, 30% lava rock, 30% Pumice, 10% fine oyster shell for calcium.
The only time I alter the mix is for trees going into refinement for shows, I’ll sub the lava rock with akadama to get finer ramification.
Reach out if ya have questions. You can find me in FB, or instagram kyle Purvis, Honey Hill Bonsai Growers.
I have used a variety of zeolite that’s called clinoptilolite in my soil mixture for some years, maybe about 25%. I couldn’t find any real negative impact on plant growth but also I didn’t witness any kind of miracle using it.
The good thing about it: It was very stable and didn’t break down, it had good water holding capacities and aeration.
Why I stopped using it:
I couldn’t find any real benefits in comparison to pumice and akadama (I don’t consider the breaking down of akadama as a disadvantage)
I didn’t like the colour (it is blue when moist)
It still is kind of an experimental substrate (There is much less empirical evidence that it promotes the growth you need for high quality bonsai than there is for akadama and pumice).
Most importantly: My mentor who knows a lot more about bonsai than me argued that the CEC of zeolite is VERY high (which is true) which can lead to nutrients being locked in and not released to the plants anymore (which I couldn’t verify yet but it is a quite logical conclusion drawn from the very high CEC).
Also: To my knowledge there are some kinds of cations are bound by zeolite much stronger than others. Among those that are bound easiest and strongest are heavy metals such as cadmium and radioactive elements (which is why zeolite is used for decontaminating soils after catastrophes like that in Fukushima). This means that these poisonous elements will over time accumulate in your soil, especially if you use mineral fertilizer, as the phosphorous in this kind of fertilizer was most likely mined from soils that are naturally very high in uranium which is still present in this fertilizer.
So all in all: I didn’t find any negative impact nor any positive. But from what I know about it with my lay knowledge in soil chemistry there is a risk in using it which cannot be justified by the non-existing advantages of this soil component. So in the end I’d rather stick to my pumice / akadama mix.
