Lava rock as replacement for perlite - lazy grower

[Manbris]

Hi!

Would like to do some sense checking here on my soil plans.

Location- Yorkshire U.K.
Watering schedule- lazy/free style- once a day in growing season and nothing in U.K. wet season: they sit on grass in my backyard see pic attached.

1. For prebonsai material or in early development materials in nursery cans or pond baskets-

70 percent perlite, 15 percent mini line bark and 15 percent coco coir or home made compost mix with top soil
- for maples add 10 percent vermiculite

2. For late stages or in a bonsai pot trees

Option A: use soil from https://www.kaizenbonsai.com/pages/bonsai-soil

Option B: replace perlite in above mix with aquarium lava rock from eBay minus compost - so lava, mini pine bark and coco coir.

Unfortunately pumice is too expensive near me. Would you recommend option A or B here for trees going in bonsai pot?

Please advise- thanks!

 

[RoadManDenDron]

Kaizen soil is alright, most people I know who do use it will add extra akadama to it, particularly for deciduous trees

Checkout ibuki premixed akadama, lava, pumice. I used to pick mine up at Doncaster

I use perlite and vermiculite with seedlings but not much else, it's a bit too lightweight for heavy watering and outdoor use, it just floats to the top

Also please consider getting your trees off the ground, even if you just put each one on a block! a couple rows of benches would be even better

 

[Manbris]

Kaizen soil is alright, most people I know who do use it will add extra akadama to it, particularly for deciduous trees

Checkout ibuki premixed akadama, lava, pumice. I used to pick mine up at Doncaster

I use perlite and vermiculite with seedlings but not much else, it's a bit too lightweight for heavy watering and outdoor use, it just floats to the top

Also please consider getting your trees off the ground, even if you just put each one on a block! a couple rows of benches would be even better

Thanks so much for the advice.

Could you please elaborate a bit more on getting trees off the ground? - I thought it would be good for prebonsai trees to be able to grow into the ground via drainage holes?

will check out the ibuki soil mix- where about in Doncaster? Could not find it.

Thanks a lot!

 

[houterig]

My reason for not putting pots on the ground is the amount of insects that nest under and eventually in the pot, I wonder what others would be.

 

[Glaucus]

This guy was using very high levels of perlite for pine seedlings:

And getting good results. To me, perlite should be around 30 to 50%. If it is more, I get worried it gets too light and the perlite may float or blow away, because the perlite is not embedded in something else.

Comparing perlite with lava, lava holds less water than perlite. So you cannot compare one to one, or replace one of them with the other and expect the same overal mixture properties.
Perlite can hold a lot of water, more even than pumice, but it has the habit of wanting to drain it as well. Vermiculite is different in that it can hold on to water longer.
Therefore, vermiculite is said to be used for seedlings to hold on to moisture. And perlite is said to be added to soil to add air pockets and drain away the water.
In terms of water retention, lava rock is less than akadama. Which is less than kanuma. Which is comparable to perlite and pumice.

Are you asking for a potting mixture that allows you to water less? So retains more water than the standard akadama/pumice/lava 1:1:1 people like to use for pine bonsai? But is also cheaper than Japanese imported stuff?
For material you are propagating and growing out, and is not in bonsai pots, you could definitely use a more traditional nursery mixture.

 

[Manbris]

This guy was using very high levels of perlite for pine seedlings:

And getting good results. To me, perlite should be around 30 to 50%. If it is more, I get worried it gets too light and the perlite may float or blow away, because the perlite is not embedded in something else.

Comparing perlite with lava, lava holds less water than perlite. So you cannot compare one to one, or replace one of them with the other and expect the same overal mixture properties.
Perlite can hold a lot of water, more even than pumice, but it has the habit of wanting to drain it as well. Vermiculite is different in that it can hold on to water longer.
Therefore, vermiculite is said to be used for seedlings to hold on to moisture. And perlite is said to be added to soil to add air pockets and drain away the water.
In terms of water retention, lava rock is less than akadama. Which is less than kanuma. Which is comparable to perlite and pumice.

Are you asking for a potting mixture that allows you to water less? So retains more water than the standard akadama/pumice/lava 1:1:1 people like to use for pine bonsai? But is also cheaper than Japanese imported stuff?
For material you are propagating and growing out, and is not in bonsai pots, you could definitely use a more traditional nursery mixture.

Thanks a lot for the reply. Really informative.

More or less, I am asking for a potting mix that is cost effective for growing out bonsai trees - not in bonsai pots. Also suitable for raining/wet weather we have here. Yeah probably an intermediate step between transitional nursary soil and expensive bonsai soil.

For the future, is it more efficient for us to prepare bonsai mix or we go for ready made soil mix? Also I do not understand the role of akadama - if we already use pumice and lava…

 

[Glaucus]

Well, growing plants in containers to get them larger is a solved problem. Copy what the local nursery industry does. And they put tarp or plastic on the area where they have their containers, so they are not on the ground directly. Could be for bugs reasons. Not sure. For trees, up to a certain size, people prefer containers. And after that, ground planting.
For containers and bonsai, people seem to prefer air prune pots or pond colanders.
And maybe you need to adjust the soil mixture to sit in haflway between your bonsai pot mix, and the mixture a plant nursery would use, to make the transition more natural. So as you say.
But if you bare root a pine when you put it in it's first bonsai pot, you may not care what you grew it in originally. Not an expert on pine bonsai or yamadori so maybe other people can comment on that. Bare rooting pines generally is not recommended, I believe.
Generally, for non-bonsai pots, it seems like most plants prefer to grow in a mixture with some soil, peat, compost. And not in pure substrate. But your watering and fertilizer regime always has to match your potting mixture.
People often swear on 100% substrate with lava and akadama. But I don't see why you would want to propagate and develop material using substrate. Especially when it is very expensive and often has to be imported from Japan.
Once you put a plant in a bonsai pot ,you generally do not want it to grow too much anymore. And the game changes anyway. Also because of the smaller root wall the plant has. When you start to root restrict a plant, and provide it a fertilizer that's almost deficient in nitrogen, the plant starts to grow differently. And you get more coarse compact growth with smaller needles. Where during development, you want the longest fattest candles with the longest needles you can get, dark green fully pumped up with ample nitrogen.

Akadama is preferred for bonsai because it decomposes as the plant grows, allowing for a finer root system as the plant matures. This means the water-oxygen ratio changes as the root ball grows, making the mixture retain more water as the tree needs more water. And also because akadama is dirt cheap, in Japan. Which also means you have to repot your bonsai when the akadama has broken down too much.

But for pines, akadama is too wet. So they add lava. Not entirely sure why the pumice is also there.

 

[Manbris]

Well, growing plants in containers to get them larger is a solved problem. Copy what the local nursery industry does. And they put tarp or plastic on the area where they have their containers, so they are not on the ground directly. Could be for bugs reasons. Not sure. For trees, up to a certain size, people prefer containers. And after that, ground planting.
For containers and bonsai, people seem to prefer air prune pots or pond colanders.
And maybe you need to adjust the soil mixture to sit in haflway between your bonsai pot mix, and the mixture a plant nursery would use, to make the transition more natural. So as you say.
But if you bare root a pine when you put it in it's first bonsai pot, you may not care what you grew it in originally. Not an expert on pine bonsai or yamadori so maybe other people can comment on that. Bare rooting pines generally is not recommended, I believe.
Generally, for non-bonsai pots, it seems like most plants prefer to grow in a mixture with some soil, peat, compost. And not in pure substrate. But your watering and fertilizer regime always has to match your potting mixture.
People often swear on 100% substrate with lava and akadama. But I don't see why you would want to propagate and develop material using substrate. Especially when it is very expensive and often has to be imported from Japan.
Once you put a plant in a bonsai pot ,you generally do not want it to grow too much anymore. And the game changes anyway. Also because of the smaller root wall the plant has. When you start to root restrict a plant, and provide it a fertilizer that's almost deficient in nitrogen, the plant starts to grow differently. And you get more coarse compact growth with smaller needles. Where during development, you want the longest fattest candles with the longest needles you can get, dark green fully pumped up with ample nitrogen.

Akadama is preferred for bonsai because it decomposes as the plant grows, allowing for a finer root system as the plant matures. This means the water-oxygen ratio changes as the root ball grows, making the mixture retain more water as the tree needs more water. And also because akadama is dirt cheap, in Japan. Which also means you have to repot your bonsai when the akadama has broken down too much.

But for pines, akadama is too wet. So they add lava. Not entirely sure why the pumice is also there.

Thanks so much! Great information - totally a lot to learn and understand (spend some relaxing play time in the garden)

 

[RoadManDenDron]

Thanks so much for the advice.

Could you please elaborate a bit more on getting trees off the ground? - I thought it would be good for prebonsai trees to be able to grow into the ground via drainage holes?

will check out the ibuki soil mix- where about in Doncaster? Could not find it.

Thanks a lot!

Yea I suppose it is what it is if you're hoping for escape roots,

I think I mentioned before to you about there used to be a show and boot sale type sale area in Doncaster, it was fantastic but they stopped it this year,

There are now a few other popping up to replace it but they're a bit further from Yorkshire

There was one in penkridge cattle market and there is one at Newark

I'm yet to see the ibuki guy at either tho,

I'm not sure if you can buy from them online or maybe contact them and find out what shows they are attending

For growing out trees, a nursery mix is fairly successful, I would just take care not to neglect root work early on, you don't want to exactly copy the nursery practices

 

[Manbris]

Yea I suppose it is what it is if you're hoping for escape roots,

I think I mentioned before to you about there used to be a show and boot sale type sale area in Doncaster, it was fantastic but they stopped it this year,

There are now a few other popping up to replace it but they're a bit further from Yorkshire

There was one in penkridge cattle market and there is one at Newark

I'm yet to see the ibuki guy at either tho,

I'm not sure if you can buy from them online or maybe contact them and find out what shows they are attending

For growing out trees, a nursery mix is fairly successful, I would just take care not to neglect root work early on, you don't want to exactly copy the nursery practices

Thanks very much. Will follow up on the shows.