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cwavec · March 28, 2017

I've also looked at a little on these soils. It seems the water-holding capacity
is a little bit of a "trick".

One explanation has it something like rice krispies. When the fluid molten
rock is expelled, it goes from being under extreme pressure to being under
no pressure. Consequently, it suddenly expands and takes on a sponge-like,
porous character. This material can hold a lot of water that it will pick up
from underground flows. But it is deep.

Looking at the consistency of the soil being tilled in the above videos, you can
see that this surface soil is not holding any water, even if it could.

So, I'm hypothesizing that the plants must be adapted to sending deep
roots to tap the massive amounts of water farther underground. This
brings us to the idea of growing these in containers. I don't think it would
be feasible to duplicate such a structure. Probably one would have to rely
on a more or less normal container soil. Soggy, I guess wouldn't do it.
Do whatever amendments would be needed (sand?) to make it very
well-draining and plan to water frequently.

That's my guess. Anybody want to add to it?

March 28, 2017	#42
cwavec Tomatovillian™ Join Date: May 2016 Location: PA - 5b Posts: 92	Volcanic Soil I've also looked at a little on these soils. It seems the water-holding capacity is a little bit of a "trick". One explanation has it something like rice krispies. When the fluid molten rock is expelled, it goes from being under extreme pressure to being under no pressure. Consequently, it suddenly expands and takes on a sponge-like, porous character. This material can hold a lot of water that it will pick up from underground flows. But it is deep. Looking at the consistency of the soil being tilled in the above videos, you can see that this surface soil is not holding any water, even if it could. So, I'm hypothesizing that the plants must be adapted to sending deep roots to tap the massive amounts of water farther underground. This brings us to the idea of growing these in containers. I don't think it would be feasible to duplicate such a structure. Probably one would have to rely on a more or less normal container soil. Soggy, I guess wouldn't do it. Do whatever amendments would be needed (sand?) to make it very well-draining and plan to water frequently. That's my guess. Anybody want to add to it?