Anyone else primarily use Cactus-Soil for bonsai?

[エドガー]

Just watched this guys' soil-series today:

He too mentions (and tests) that his 8822 def breaks down into mush. But, in his freeze-thaw test, it doesn't break down and turn mushy nearly as much as akadama.

But, I kinda question the pumice he's using... it looks very soft and brown, looks exactly like Hyuga (Japanese pumice). US pumice is much whiter, harder, sharper, probably fired at higher temps, more visible porosity - US white pumice is almost kinda like black-lava-rock/scoria but a bit softer/milder.

Just read his corrected video descriptions... and I was correct... he wasn't using US pumice... he was using Kanuma.

 

[rockm]

Just watched this guys' soil-series today:

He too mentions (and tests) that his 8822 def breaks down into mush. But, in his freeze-thaw test, it doesn't break down and turn mushy nearly as much as akadama.

But, I kinda question the pumice he's using... it looks very soft and brown, looks exactly like Hyuga (Japanese pumice). US pumice is much whiter, harder, sharper, probably fired at higher temps, more visible porosity - US white pumice is almost kinda like black-lava-rock/scoria but a bit softer/milder.

Um, you get a lot of freezing weather in Orange Co., cali? There is a big difference in how soil ingredients perform in freeze/cold cycles as opposed to frost free. Also, FWIW, I've been using kiryu (similar volcanic Japanese clay similar to kanuma)/Akadama mix for imported azaleas for a few years. The grade of Akadama and kiryu doesn't turn to mush immediately--but over a period of years it does--which it is mostly SUPPOSED to do. That break down coincides with repotting/root development. Satsuke azaleas have a relatively constant two to three year repotting cycle.

Additionally, the video ranks granite as #1 on its ability to stand up to the freeze/thaw cycle. Crushed granite (specifically TURKEY grit in various grades) was a primary soil ingredient in the eastern U.S. for decades. Even the National Bonsai and Penjing Museum in D.C. used a granite-based mix for years. It has gradually fallen out of favor as it is extremely heavy and doesn't retain ANY water and has a very low Cation Exchange. Mixes using it relied on heavier percentage of organics, which tended to break down, resulting in mushy soil at the bottom of pots that killed roots. That is why things have shifted towards haydite and other more porous "hard" materials in soil. They hold water and release it evenly, don't break down like organic, but also have a higher cation exchange.

Pumice is similar, but it depends on what kind of pumice. It comes in a wide variety of forms...including in the U.S.

 

[エドガー]

“Um” , obviously, no freezing weather here… but it does show and represent its' maximum/total/possible durability and wear&tear, even for non-freezing conditions too. You don't need freezing conditions to wear and weather things. Bacterial breakdown, night & day temp shifts, humidity & dryness shifts, water weathering, friction compaction and gravity, etc. will have similar effect.

Yes, I know akadama and other specialty jdm materials breaking down, is what it’s supposed to do for finer root-ramification/development, as the fine roots actually grow inside the fissures and later crack the clay particles smaller more and more. I know Akadama and other Japanese materials also have a very good CEC (at least the raw grade ones, that aren’t super high temp fired, baked to a point of total sterility).

But, if you think about it, organic material will also allow and promote for root development and also require re-potting around the same time as akadama. So, when experts say, “bonsai will just die and roots will just rot in compacted organics/soil, organic material need repotting, so organics is very bad for bonsai” ...doesn’t the same hold true for akadama, other Japanese clay materials and other inorganic "harder" materials, that also break down and stops percolating and draining easily?

Yeah… I’m not really attracted to using granite/rock for soil-mixes. Too heavy, no water retention, no CEC.

At least organic material has very good water retention for those hot and dry climates (Southwest US area, Australia, etc.) and also very good CEC. But, yes, I understand it isn’t ideal because it turns into mush (but even some inorganics turn to mush).

That’s why I too am interested in shifting towards the “harder materials” like you mentioned… they still retain/release water, don’t turn into mush like organics, promote drainage by being a big aggregate particle in a mix and also have CEC.


My only concerns are:
Which “hard materials” and DE brands are the best and don’t turn into mush easily? ...and I'm also concerned about not using organics at all (ie: using 100% inorganic mix) in a hot hot dry climate without needing to water daily or multiple times per day.


Also another question if anyone knows:
Will DE (or a 100% inorganic mix with a lot of DE, maybe 30-50% DE) in deep/big nursery pots (5-15gal), allow me to go without watering daily? For how long, how many days, without watering will it still stay sufficiently hydrated and moist enough to keep a plant alive/healthy?
Will “100% inorganic mix with a lot of DE” allow me to water only 2-3x per week during the summer?



Hate on it as much as you like... but I love cactus-mix (at least the EB Stone brand that I use, and sometimes Kellogg)… it contains good stuff for SoCal climate - pumice, scoria lava rock, aged fir bark & redwood for its’ organic materials CEC and water retention, coarse sand for un-breakdown'able drainage particles. All in a nice consistent size (no huge woody pieces like when buying pine bark) and no powdery rock fines. It allows me to only water 2x per week too during summer (3x per week during heatwaves).

 

[milehigh_7]

Short answer is I can't recommend skipping days with DE. The reason is that if it gets dry it will suck the water from the roots. The only time you should skip is when you are getting rain.

As far as breaking down, it is the non-calcined that will quickly break down. Search for posts on DE under my user name and you will find lots of information.

 

[エドガー]

Thanks!

 

[エドガー]

Short answer is I can't recommend skipping days with DE. The reason is that if it gets dry it will suck the water from the roots. The only time you should skip is when you are getting rain.

Hmm... almost sounds like Turface (sucks water from the soil and roots, and not giving back water), but most likely not as much to an extent with DE.

I guess I'll pass on DE then (I don't wanna experiment and kill my trees)... and just stick with pumice+organics (via bagged cactus-mix, or blending my own mix with pumice+organics). It's been working great for me anyways.

 

[エドガー]

Gettting ready for 6 newly ordered trees and also a lot of repotting before spring... got 12 bags of cactus-soil (2 were free) and 3 bags of regular potting-soil. I like adding a touch more organic, for the super dry and hot Santa Ana winds in the summer.

I usually do and have always done 2 parts cactus-mix and 1 part potting-mix; but I guess I’ll do 4 parts cactus-mix and 1 part potting-mix this time, for more drainage.

Yes, I love cactus soil

For anyone interested.. here’s some pics showing particle and pumice size, consistency, a rough visual of percentage/ratio/proportions, etc.

As you can see, there’s tons of pumice and it looks very similar to many well known bonsai-store organic mixes that include a little organic matter (not their hardcore 100% inorganic mix options).

...and for those that keep saying, “I only use it for and it’s only good for cactus and succulents” ....well, then shouldn’t DE be only used for oil-spills and in the garage, and Turface only used for baseball fields? Lol ;P

 

[nikolaibonsai]

People can be a bit anal and zealous about soil mixes. As long as water can retain itself and drain appropriately then it really doesn't matter what it's made of.

Since I have a lot of bonsai of varying species it's easier to buy cacti mix in bulk, I also add in a bit of potting mix and have never had any issues at all. I personally prefer more organic contents so I don't have to water them every day.

 

[Arizona bonsai]

I use Kellogg cactus mix & 50% perlite. I would like to use pumice but have not yet found a good source.

 

[エドガー]

"Cactus mix" is truly good stuff and a good buy at only $8-11 per huge bag. It's sifted already of rock/pumice fines/powder, ready to go, quick to use, convenient, etc.

It's basically the exact same thing as what bonsai stores sell for like $20-30 for a tiny bag. Bonsai stores usually sell 2 kinds of soil - a "100% inorganic/aggregate mix", but they also usually have an "organic + inorganic mix" too of 40-60% organics and inorganic/aggregate (pumice, akadama, scoria, dg, coarse sand, etc.).

The latter is almost exactly the same as "cactus mix" ...cactus mix = pine and fir bark (recycled forest products), a little coarse sand and a lot of pumice (EB Stone also adds scoria lava rock).

 

[erich_raudebaugh]

I think that rockm has some very good points you should consider. I've been into bonsai for 30 years now, and like many old timers I've tried almost every soil component and substrate that there is. If I lived in California I could point you in the right direction, but rockm is right, contact some of the excellent local clubs in California! I've used cactus mix too and it really isn't very good.

You might find surprises locally. For instance, there's a mine not too far from me that supplies a type of D.E. not available anywhere else, it's tan and looks like akadama, but acts more like pumice or kanuma, and it doesn't break down (so much better than oil dry too, it doesn't suck water out as it hasn't been calcined yet still doesn't break down). There are lava fields in my state where you can collect scoria for free. There are pumice mines nearby, so it's really cheap. I wouldn't have known any of this without talking to people in the local bonsai community.

 

[Lazylightningny]

If you know how to water correctly you can grow a tree in just about anything. Inorganic substrate is a relatively recent advent. The great thing about modern substrate is that you don't have to spend years learning how to water a bonsai. If you have holes in the bottom of your container, you can't overwater a tree in modern inorganic bonsai soil. Plus, it provides more oxygen in the inter-particle spaces than organic soil.

 

[エドガー]

contact some of the excellent local clubs in California!

I've used cactus mix too and it really isn't very good.

You might find surprises locally. For instance, there's a mine not too far from me that supplies a type of D.E. not available anywhere else, it's tan and looks like akadama, but acts more like pumice or kanuma, and it doesn't break down (so much better than oil dry too, it doesn't suck water out as it hasn't been calcined yet still doesn't break down). There are lava fields in my state where you can collect scoria for free. There are pumice mines nearby, so it's really cheap. I wouldn't have known any of this without talking to people in the local bonsai community.

Local clubs, bonsai stores and bonsai people say the same thing - organics are needed in SoCal weather and Santa Ana dry winds (single digit % humidity in summer). It is the base for their soil mixes. Many here actually use "pine bark soil conditioner" as a main base, and mix in a little aggregate/pumice/dg/sand/etc. in it.

Which cactus mixes have you used??
Why do you say it isn't good?
The cactus-mixes I use is made of pumice, scoria, bark, and coarse sand. Those are all good to me imo.

Not interested in DE anymore... sounds like more of a worry/risk(might keep/take too much water instead of giving back to roots, and also breaks down just like organics anyways) and hassle(going to an extra place after nursery[an auto parts store], and also sifting it), than just using standard stuff.

Nice finds on your scoria and pumice sources. Cactus-mix has it too, lol.

 

[エドガー]

If you know how to water correctly you can grow a tree in just about anything. Inorganic substrate is a relatively recent advent. The great thing about modern substrate is that you don't have to spend years learning how to water a bonsai. If you have holes in the bottom of your container, you can't overwater a tree in modern inorganic bonsai soil. Plus, it provides more oxygen in the inter-particle spaces than organic soil.

Good points!
Yes, of course oxygen is needed and is very good for the roots (the Con of using organics I admit).

But, remember this... "it is much much easier and quicker to kill a tree from under-watering, than it is from overwatering." ~Bjorn

Under-watering can kill a tree in as little as 2-3 days in the middle of hot summer.

Over-watering can take months or years to kill a tree.

 

[Lazylightningny]

Good points!
Yes, of course oxygen is needed and is very good for the roots (the Con of using organics I admit).

But, remember this... "it is much much easier and quicker to kill a tree from under-watering, than it is from overwatering." ~Bjorn

Under-watering can kill a tree in as little as 2-3 days in the middle of hot summer.

Over-watering can take months or years to kill a tree.

You won't see Bjorn using organic substrate. He's just giving the caveat to using inorganic soil. You have to water diligently.

 

[エドガー]

Bonsai professionals and very experienced people that use organic substrate - House of Bonsai in LA (they do wknd workshops too), chasnsx/Kuromatsu bonsai (YT/blog), Herons bonsai (YT), Peter Macasieb, Hanh Baloc bonsai (YT), Hiro/Masteryo (YT)... and pretty much almost every bonsai nursery I've seen, offer/use an organic mix option (along with 100% inorganic options too of course).

Coincidentally, I just watched a video last night, with Hanh Baloc saying in one of his demos/teachings - he's been studying trees for decades and says trunks grow a lot faster/bigger/healthier in organic soils, than inorganic/akadama/DE soils. He says inorganic soils (akadama, DE, etc.) slow the trees' growth down tremendously and should only be used for almost totally completed trees, around 80-100% developed and finished trees (ie: fine ramification and fine tuning stages).

He's very blunt and frank... so I believe what he says. From his comment about organics, I assume trees grow bigger and better in organic soils maybe because organics have better CECs. Not really sure. Or maybe organics are just very similar to nature's earth.

 

[Lazylightningny]

Bonsai professionals and very experienced people that use organic substrate - House of Bonsai in LA (they do wknd workshops too), chasnsx/Kuromatsu bonsai (YT/blog), Herons bonsai (YT), Peter Macasieb, Hanh Baloc bonsai (YT), Hiro/Masteryo (YT)... and pretty much almost every bonsai nursery I've seen, offer/use an organic mix option (along with 100% inorganic options too of course).

Coincidentally, I just watched a video last night, with Hanh Baloc saying in one of his demos/teachings - he's been studying trees for decades and says trunks grow a lot faster/bigger/healthier in organic soils, than inorganic/akadama/DE soils. He says inorganic soils (akadama, DE, etc.) slow the trees' growth down tremendously and should only be used for almost totally completed trees, around 80-100% developed and finished trees (ie: fine ramification and fine tuning stages).

He's very blunt and frank... so I believe what he says. From his comment about organics, I assume trees grow bigger and better in organic soils maybe because organics have better CECs. Not really sure. Or maybe organics are just very similar to nature's earth.

Best of luck with your organic substrate!