AND WHAT ABOUT LAVA...MORE GOOD NEWS!

[August44]

I saw this article just now. Of course this is just after I, with the club, dug and screened hundreds of gallons of black lava a couple of weeks ago. This kind of news is disappointing to me as it must be to others if it is true. There are a lot of people out there that can't afford ackadama at the outrageous price that it is now. What to do....​

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Is Lava Good For Bonsai?​

crataegus Mar 10 This is a legitimate question. My master Shinji Suzuki never used lava (aka scoria), preferring just akadama and pumice. On coming back from Japan in 2006 I continued using the akadama / pumice mix and have always had strong, fine root growth with dense root masses. Joe Harris III then reported that boron toxicity in lava had limited root growth at Iseli Nursery. Similar reports came from David DeGroot, and then more recent lava scares from Ryan Neil. All of which has me thinking of the “if it ain’t broke don’t fix it” adage. Mr. Suzuki’s simple akadama / pumice mix has served me well and these stories don’t warm me to lava. Lava, aka scoria, commonly used in bonsai media​ Last year I was in conversation with my former apprentice Andrew Robson who does a lot of traveling and repots more bonsai in various soil media than I do, and he’s developed strong negative opinions about both red and black lava. Here are Andrew’s observations: As a bonsai professional who travels to work with students across North America and with a large collection of my own, I end up repotting several hundred bonsai each repotting season. One thing I've noticed is the effect of different soils in different locations across North America, and with different skill sets. While the professional bonsai community has come to the consensus that volcanic soils work best in a bonsai pot for optimal root growth, I've observed that lava grows worse roots than pumice and akadama alone. I don't utilize lava for many reasons, but the first and foremost is the root systems I routinely see in it. Almost without exception, every bonsai I've repotted where lava made up at least 30% of the soil mix has had poor roots. Oftentimes when I take these bonsai out of the container, much of the soil just falls away because there isn't the fine root mass to hold it all together. In my experience, and now the experience of my students and clients, lava isn't creating the root systems that we’re looking for. The same exact bonsai, switched to an akadama and pumice mixture, grows roots that are far superior in a much shorter period of time. There's a few other reasons I can't stand working with lava. Other than the poor root growth I see in it, it's extremely heavy compared to the alternative (pumice). It can add a lot of weight to a bonsai pot, especially a large bonsai. Lava is also hard and will destroy the sharp edge of bonsai tools with just a few repottings. Plus, it's one more material to source, purchase, sift, and mix up for our bonsai. For all these reasons, I avoid lava with a passion. Year after year I continue to see the same thing as I repot bonsai across North America: poor roots, heavy trees, and dull tools when lava is over-utilized in the soil mix. Many of the top bonsai gardens in Japan go without lava for some of the most valuable bonsai on the planet, and if those trees can thrive without it ours definitely can as well. I always encourage bonsai practitioners to keep doing what is working well for them even if it's not something I teach or practice. But over the last several years I've moved away from using lava in my own and my student’s bonsai pots, and we couldn't be happier with the results. —Andrew Robson Andrew’s findings are documented in this video:

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[NaoTK]

There are a couple myths about lava that are repeated in my bonsai community (I had this conversation with people from you article!)

Myth#1: there is boron in lava
I did some reading following our discussion on black vs. red cinder color. We are lucky the USGS already measured the chemical composition of cinder from Little Nash crater (where everyone in portland gets their lava):

https://pubs.geoscienceworld.org/gs...olocene-volcanism-of-the-upper-McKenzie-River

Myth 2: red lava and black lava have different compositions (red has more boron?)
We are also lucky that a group from New Mexico measured different colored cinder (scoria) at nearby Broken Top Mountain. They measured the magnetic properties of the cinders and inferred the temperature at which they were laid down at around 580C. Darker cinder was at a higher initial temperature and cooled slower than the red cinder, but they are of the same origin.
https://www.sciencedirect.com/science/article/pii/S0377027398000067

 

[BeepBeepBonsaiSheep]

Bummer. I got 20gal of 3/8” lava rock, haha

Maybe I’ll just chuck it and keep a gallon or 2 as possible landscaping elements

Oh, I just remembered I have a 5# bag of pumice! I’ll use that for some mame sized stuff

 

[August44]

There are a couple myths about lava that are repeated in my bonsai community (I had this conversation with people from you article!)

Myth#1: there is boron in lava
I did some reading following our discussion on black vs. red cinder color. We are lucky the USGS already measured the chemical composition of cinder from Little Nash crater (where everyone in portland gets their lava):
View attachment 476131
https://pubs.geoscienceworld.org/gs...olocene-volcanism-of-the-upper-McKenzie-River

Myth 2: red lava and black lava have different compositions (red has more boron?)
We are also lucky that a group from New Mexico measured different colored cinder (scoria) at nearby Broken Top Mountain. They measured the magnetic properties of the cinders and inferred the temperature at which they were laid down at around 580C. Darker cinder was at a higher initial temperature and cooled slower than the red cinder, but they are of the same origin.
https://www.sciencedirect.com/science/article/pii/S0377027398000067

In the chart above, which major element is Boron Pls

 

[Cruiser]

Interesting write up. I’d like to hear more opinions on this! That 33 gallons of lava rock may not need to be sifted after all…

 

[NaoTK]

In the chart above, which major element is Boron Pls

Boron is B and there is none! That is the point. Boron is actually very rare on Earth. It is found in the crust and water in very small concentrations and deposits are usually found where huge lakes or oceans dried up, concentrating the boron (such as the deserts of California "20 mule team" borax)

 

[HighDesertBonsai]

Hmmm, interesting article. I personally have never experienced poor root development with lava as an additive. For example, I repot all of my tropicals each year and they all are in a 1:1:1 mix with lava, pumice, akadama, or pine bark. They all fill the pot each year and must be repotted before spring they are in full sun, top-dressed and wrapped when the heat rises.

I am sure there's lots of evidence to support the claims made here. Just like many things in bonsai the variables, microclimates and misconceptions of "what should be done" or "what is actually done" are all potential pitfalls.

In my opinion, I think the location and exposure of your tree(s) is more likely the issue.

Another thing to consider is whether trees are top dressed properly for hotter weather and were tree containers wrapped to prevent overheating. All are variables with huge potential for negative impact on water mobility in the tree and potted environment.

just my $.02

 

[mook1178]

Boron is B and there is none! That is the point. Boron is actually very rare on Earth. It is found in the crust and water in very small concentrations and deposits are usually found where huge lakes or oceans dried up, concentrating the boron (such as the deserts of California "20 mule team" borax)

Could it be that they just did not measure for Boron? Do you have the methods section of your citation? If measured and there is none, that is usually reported as 0.0. If not measured it is usually not listed in the chart. The fact it is not listed leads me to believe it was not measured.

 

[HorseloverFat]

In the chart above, which major element is Boron Pls

Well...
Boron...If we think back to biology/chemistry/organic soil comp... From the periodic table is B.... Has been for MANY years...

He's saying there IS none, traceable.

EDIT: I see this has been addressed.

 

[NaoTK]

Could it be that they just did not measure for Boron? Do you have the methods section of your citation? If measured and there is none, that is usually reported as 0.0. If not measured it is usually not listed in the chart. The fact it is not listed leads me to believe it was not measured.

I will leave this for you to look into... I get your point but XRF is fully capable of detecting boron and it is reporting single ppm digits of trace elements (borates is what you would find not elemental boron)

 

[mook1178]

I will leave this for you to look into... I get your point but XRF is fully capable of detecting boron and it is reporting single ppm digits of trace elements (borates is what you would find not elemental boron)

I'm not fully versed on XRF. Does the prices report what if find in the sample or did the user have to ask it to look for boron in the sample? That would definitely change the way it is listed in the chart. If XRF reports what it finds, then not being in the chart is a good indication of B not being present.

I was definitely looking for borate as that is found naturally in seawater.

 

[Colorado]

Interesting points.

I can see why Andrew Robson wouldn’t find lava desirable - he is working with mostly deciduous species. I don’t use lava on deciduous either. It makes the mix a little bit too “dry” for deciduous in my opinion.

I’ll probably keep using it for conifers though. Haven’t had any problems with it (that I know of).

 

[Mike Corazzi]

I've started using lava with the smaller aka MIX. NEVER straight akadama..!!! No longer even the MEDIUM mix.
The smaller particles along with larger lava pieces seem to hold a bit more attraction for roots but the lava keeps them from mucking up like akadama.

After all the years, I find used soil to have some pretty good merit. PROVIDED you use some sense in sifting and selection.

 

[Apex37]

It’s interesting because they’ve discussed this before on Bonsai Wire. Jonas did a write up on one nursery in Japan where all they use is straight lava for everything and we’re very successful with growing things.

https://bonsaitonight.com/2020/03/03/onumas-mini-bonsai-growing-techniques/

I’ve used lava in mixes with tropicals and conifers with no issues (so far, still newer to all this), but I tend to not include it in my other mixes except maybe smaller screened sizes used for cuttings.

 

[Kievnstavick]

I am also a fairly new person when it comes to bonsai and the soil mixtures. What I have witnessed so far is purely observational notes with no scientific(-like) testing. Maybe I'll learn something different in the future or the school of hard knocks will come in swinging.

I agree with another post on not seeing any ill effects of using scoria in both my own trees and others I have seen repotted. I have a jalapeño plant (plus bells amd banana peppers) in my own mix of bonsai substrate (approximately 32% Pumice, 32% Scoria, 30% Bark. And 6% Horticultural charcoal) as a way to overwinter it in doors as well as practice repotting techniques on a quick growing plant. The jalapeños loves growing its roots in the scoria and bark more then the pumice.

I also have a test tree in 50/50 scoria and pumice (as I wanted to repot but didn't have all the ingredients yet). The tree had completely filled its nursery container even with 2 emergency reports dues to heavy winds within 2 years.

I visited a few Bonsai clubs while on a trip to Hawaii and they make heavy use of scoria in their mixes. I saw anywhere from 30 to 60 percent Scotia and the remaining as half akadama and bark. The few people I have spoken with don't use pumice due to supply issues.

I would like to believe Andrew knows what he is doing, but the description of the substrate falling apart at the time of repotting sounds like the tree was repotted too soon. Maybe he is exaggerating his statement to prove a point. It just sounds inherently wrong to me without more context to his statement.

Additionally, I think the biggest key here is knowing your climate and knowing your substrate ingredients. Why they are included and how plants interact with them.

 

[August]

@Kievnstavick I agree with your take on this; whenever I see talk like this fron the pros it almost feels intended to strike fear into the heart of hobbyists. With all the soil experiments that Mirai had been up to I would be really surprised if they don't push a premium "new technology" soil mix in the next few years. Not a criticism on them but an observation. I bet it'll be expensive.

I use about 25% lava and this did scare me when I first read it. I have to remember the Walter Pall way; you can grow in ball bearings if your watering practice is correct.

And also species requirements; there is no one mix that any plant will thrive in. For example I have heard that Coffee strongly prefers to grow in volcanics; probably thrives with scoria in the mix. Strange example but it was on my mind.

I'm a newbie but ive had no issue with lava and its readily available here. Then again I use a fair bit of 8822 and I have heard more than enough of other peoples opinions on that.

 

[MaciekA]

Onuma’s results speak volumes because he doesn’t just grow in lava, he grows absolutely everything in lava with great results.

But he also doesn’t grow what Michael is growing, which is mature slowed down bonsai.

Add to this that Jonas recently told me that he is getting wonderful results in lava and prefers it to pumice — again for specific types of growing projects that do not resemble what Michael or Andrew (or perhaps many of you) are growing.

For my own results I’ve grown lodgepole yamadori in pure lava and these are easily some of the healthiest plants I have by a mile.

The least interesting parts of soil discussions by far are characterized by a “checkmate !! it’s bad, just as we suspected!” flow of thinking. We should be treating all discussions about volcanic media as a very sparse and infrequent sampling of a dataset whose breadth we’ll never fully appreciate because there are so many factors at play, again not the least of which is that we are all doing very different things. I’m not surprised Andrew doesn’t like the idea of putting a mature ramified japanese maple in pure lava. Onuma probably wouldn’t either.

It just isn’t useful to get a definitive globally-applicable statement that claims to cover absolutely all cases and all situations when we have evidence from multiple well-regarded growers (like Onuma, like Jonas, etc) that the stuff not only works, but stands on its own in a homogenous application and produces good results in certain types of cases. I study under some of the people mentioned above and respect them, but I also take into account they’re not growing everything in every way for every project type. Michael and Andrew’s projects don’t overlap with Onuma’s much, and Jonas is in a different climate from us where the added drainage may be saving him a lot of headaches in a more permanently-humid growing location. There is a pretty big difference between early development in colanders and mature trees in bonsai pots.

Beware of one size fits all discussions and “checkmate!”

 

[MaciekA]

And also species requirements; there is no one mix that any plant will thrive in.

I think this is a good point and you can extend it even further by asking whether the notion of “thrive” is even a common goal for everyone in exactly the same way. For example, I might want to step on the gas pedal and get chunky colonizing roots as fast as possible. Or I might want to get scaling ramified roots and slow the tree down. Or I might be trying to literally reproduce what lava is already doing to some lodgepoles in the Cascades, where you can find magical “elderly seedlings” that would surely look different if they’d grown in a different soil (ie one that held a lot more water and greatly magnified their vigor — goodbye magically dwarfed seedling!)

I think a lot of nuance is lost when the discussion fixates on “care” as opposed to “precise engineering of trees by using whatever knobs and levers we can”. Soil affects morphology. Lava opens up possibilities for some, but causes trouble for others.

 

[leus]

I'd like to know if there is a way to create a *good* akadama sustitute artificially (I mean, source clay and minerals and put it in an oven and sift it).

Also, I know that there is a region in my country with a lot of volcanic clay that looks suspiciously like akadama quarries, so I wonder if there is a way to have it tested and compared with real Akadama. That stuff is stupidly expensive to get here and I'm in principle against the idea of transporting dirt from one continent to another.

 

[Ruddigger]

My teacher uses 80% black lava and 20% akadama in all his trees. He has a small mountain of lava in his yard.