Any opinions on zeolite?

[Carapace]

I have been using a mix of about 40% zeolite, 30% lava rock, 10% pumice, 5% perlite and 15% pine bark (it's a mess I know) for the last 1 year and it's been going pretty well, except for a few deaths which I think happened because of overwatering and sometimes forgeting to water a tree. I am curious about your opinions on zeolite, I haven't really seen anyone use it but from what I've read on the internet it should be really good: decent water retention, really good cation exchange, doesn't break down and it's also pretty.
So has anyone used zeolite before?

 

[RJG2]

The are some previous discussions here around its use:

Search results for query: Zeolite

www.bonsainut.com

@Maros uses it extensively, and his trees speak for themselves.

 

[Maros]

I have been using a mix of about 40% zeolite, 30% lava rock, 10% pumice, 5% perlite and 15% pine bark (it's a mess I know) for the last 1 year and it's been going pretty well, except for a few deaths which I think happened because of overwatering and sometimes forgeting to water a tree. I am curious about your opinions on zeolite, I haven't really seen anyone use it but from what I've read on the internet it should be really good: decent water retention, really good cation exchange, doesn't break down and it's also pretty.
So has anyone used zeolite before?

I use it for quite some time. and for deciduous trees I have it works well.
Question is fraction. I would recommend 4-8 mm for bigger trees, and 2,5-5 mm for smaller trees(below 30cm aprox)
Otherwise I see no problem with it.
If you have any specific questions fire them at me.

 

[ShadyStump]

I recently got a bag to test out, and have had few problems so far. Maros filled me in as well when I posted about it. This is my first season with it, so much to be seen still.

I agree with him on the particle size to an extent. In my climate I definitely need smaller particles if I'm not going to water 3 times a day in summer. I tend to include allot of organics in my mixes, largely for that reason but also others.
in that context then, so far I feel it's much better than perlite (not hard to do) or Napa 8822 and similar products. It doesn't hold near as much water, but doesn't break down or compact immediately either.
My caution is when using it without mixing with organics or other materials. It drains VERY freely, and takes allot to saturate it when watering normally. When you fertilize, the vast majority will go right out the bottom. I do recommend mixing more absorbent materials into it to combat this sort of thing.
One last thing, it has a relatively high pH. You'll want plenty of peat or the like if you have acid lover trees.

 

[Carapace]

I was thinking of replacing the perlite and bark with vermiculite, I feel that the pine bark got mushy really fast and there were some really wet spots and some really dry spots, would vermiculite help with that?

 

[Maros]

I recently got a bag to test out, and have had few problems so far. Maros filled me in as well when I posted about it. This is my first season with it, so much to be seen still.

I agree with him on the particle size to an extent. In my climate I definitely need smaller particles if I'm not going to water 3 times a day in summer. I tend to include allot of organics in my mixes, largely for that reason but also others.
in that context then, so far I feel it's much better than perlite (not hard to do) or Napa 8822 and similar products. It doesn't hold near as much water, but doesn't break down or compact immediately either.
My caution is when using it without mixing with organics or other materials. It drains VERY freely, and takes allot to saturate it when watering normally. When you fertilize, the vast majority will go right out the bottom. I do recommend mixing more absorbent materials into it to combat this sort of thing.
One last thing, it has a relatively high pH. You'll want plenty of peat or the like if you have acid lover trees.

I agree with your assessment for parts which I have experience with. If you want more water retention fraction bellow 4mm makes sense. Watering bit more is necessary, but it is not so big issue if you do not let the substrate dry completely anytime, what I prefer to do( I would like to stress that 95% of my trees are deciduous).

I generally mix rough peat into substrate, about 20% mostly.
Fertilizing is no-brainer, you better dose more as in most inorganic substrates. I rely on slow release ferts for that part.

I was thinking of replacing the perlite and bark with vermiculite, I feel that the pine bark got mushy really fast and there were some really wet spots and some really dry spots, would vermiculite help with that?

I couldn't provide any recommendation for this issue since I have no experience with vermiculite.

 

[MaciekA]

I have a potted rosemary in front of my house which is happily in zeolite. It drains just as fast and furious as @ShadyStump says it does, which works out well for the rosemary, especially since that's a north-facing location. I would feel safe mixing this into other bonsai soil mixes, but it's been a while since I've seen zeolite anywhere I shop, and I've got a big supply of pumice/akadama/lava.

 

[ShadyStump]

The stuff I got I found online marketed as a nontoxic traction aid for ice. Idea struck me when someone mentioned finding lava marketed for similar uses in Canada, so I went digging online.
Zeolite is also sold as a filter medium for swimming pools. Fines can occasionally be found as soil amendment I've read, but I think that's on farm scale because I've never found it online under lawn and garden or the like.