Did I fix what was not broken?

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So I tried something with my substrate mix. Cactus mix alone was working fine, but as perlite was around the same expense, I figured I’d mix it in maybe a third to a half, to get better aeration. That was my theory, at any rate. I just thought the cactus mix alone retained too much water.

I’m thinking I should have come to the forum and run this idea by someone first lol are there any disadvantages (or advantages) to adding a good deal of perlite to cactus mix, using that as a moderate cost mix for small bonsai? I notice maybe it might be too loose, at least for small plants in the once a year gale winds we get here. Should I maybe just use less perlite? Or will this mix not work?
 
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I'm super anti perlite, mostly cuz it floats, but also cuz it's too white. It's that white privilege makes it float to the top.😛

The density of "potting soil" keeps it in place, but without that, in our situations, a torrential rain can easily make a mess of it.

Also, if you come to a time where dunk watering becomes necessary, it prevents it from going well.

Wish it was perheavy.

Sorce
 
I prefer pumice over perlite. However, perlite chemically is actually made from pumice that was "exploded" by adding water, then flashing it to steam. Pumice is heavier than Perlite, makes a better, more stable substrate.

In the interim, until the next round of repotting, you can add a thin layer of long fiber sphagnum moss to the surface of the pot. The moss will hold the perlite in place.

Perlite is excellent for large training pots, because it is so light. I use perlite for 10 and 20 gallon pots where I am trying to grow out or size up some stock with trunks that are too slender. Perlite does have its uses.

In a shallow bonsai pot, perlite is just too light, and will be unstable because it floats so easily. For shallow pots I recommend pumice, or lava or granite grit as in poultry grit. My local feed store stocks a beautiful "purple" colored quartzite as poultry grit, brand name "Cherrystone" quarried in New Ulm, Minnesota. It makes a great topping for a bonsai pot that is not going to be covered with live moss. Out west you can get decomposed granite, which has a nice warm brown color. Unfortunately, granite grit quarried in Georgia is an ugly, stark white, with black flecks.

Look around, you should be able to source a couple different aggregates to use as bonsai potting media. A building supply place, or an industrial supply shop that carries different aggregates for sand blasting can get you a very interesting array of aggregates to add to a potting mix.

I do like pumice, as a good "base" for any mix. My mixes are all at least 50% pumice.
 
I prefer pumice over perlite. However, perlite chemically is actually made from pumice that was "exploded" by adding water, then flashing it to steam. Pumice is heavier than Perlite, makes a better, more stable substrate.

In the interim, until the next round of repotting, you can add a thin layer of long fiber sphagnum moss to the surface of the pot. The moss will hold the perlite in place.

Perlite is excellent for large training pots, because it is so light. I use perlite for 10 and 20 gallon pots where I am trying to grow out or size up some stock with trunks that are too slender. Perlite does have its uses.

In a shallow bonsai pot, perlite is just too light, and will be unstable because it floats so easily. For shallow pots I recommend pumice, or lava or granite grit as in poultry grit. My local feed store stocks a beautiful "purple" colored quartzite as poultry grit, brand name "Cherrystone" quarried in New Ulm, Minnesota. It makes a great topping for a bonsai pot that is not going to be covered with live moss. Out west you can get decomposed granite, which has a nice warm brown color. Unfortunately, granite grit quarried in Georgia is an ugly, stark white, with black flecks.

Look around, you should be able to source a couple different aggregates to use as bonsai potting media. A building supply place, or an industrial supply shop that carries different aggregates for sand blasting can get you a very interesting array of aggregates to add to a potting mix.

I do like pumice, as a good "base" for any mix. My mixes are all at least 50% pumice.
Love that " Cherrystone granite" goes so well with black lava and Akadama for aesthetics. The grey pumice is a great substrate, the only drawback from my point of view is the colour. I often forget to use pumice in the top layer of the substrate for some reason.
 
Love that " Cherrystone granite" goes so well with black lava and Akadama for aesthetics. The grey pumice is a great substrate, the only drawback from my point of view is the colour. I often forget to use pumice in the top layer of the substrate for some reason.
Thanks all! I have pumice, though I thought it was better for bigger pots. So I’ll use it As for lava rocks, I bought a large bag for a fraction of the price of smaller bags I saw on Amazon, only the bag is about half larger pieces. Will that work? If not, can I just break up the big pieces, or pick out the smaller pieces?

Hmm… so if there are no torrential rains, or need to dunk water yet, will the plants be safe, and not need potting, for the moment at least? And on that subject, when is dunking a big Kant required?
 
Thanks all! I have pumice, though I thought it was better for bigger pots. So I’ll use it As for lava rocks, I bought a large bag for a fraction of the price of smaller bags I saw on Amazon, only the bag is about half larger pieces. Will that work? If not, can I just break up the big pieces, or pick out the smaller pieces?

Hmm… so if there are no torrential rains, or need to dunk water yet, will the plants be safe, and not need potting, for the moment at least? And on that subject, when is dunking a big Kant required?
The key with substrate components is to saeivethem to the correct size for the intended use. In other words the material can be used if you sort it to the size needed for your purpose. Some may be useful for landscape, some for drainage layer, some for medium size mix and some for smaller mix. Soil Sieves are important tools.
 
Thanks to all once more. I just have one more concern. I was under the impression that perlite is good for aeration. Though it seems to me the pots are staying damper longer with perlite. Could this be the case?

I switched over to cactus mix and pumice (will this mix work well?) and researching other cost efficient inorganic components. Am I right about the perlite, that it seems to have the opposite effect as intended? Is this possible, such that I should quickly re-pot to another substrate?
 
I switched over to cactus mix and pumice (will this mix work well?)
Cactus mix has no defined composition. In some brands you will find only rocky inorganic substrate, whereas others will mostly be shredded organics with a handfull of pumice / perlite mixed in. As such, it is hard to tell what you have. Any open, welldraining substrate would do. Make sure you sift out the fines. The amount of organics you want i your mix is personal preference, climate (Drier: More) and lifestyle (How often can you water) related.

I was under the impression that perlite is good for aeration.
Anything coarse that creates airspaces will do this

Is this possible, such that I should quickly re-pot to another substrate?
Hardly ever is a quick-repot needed. Adjust watering & position to the substrate you have. If you are uncomfortable with the substrate, repot at the tie you would normally repot.
 
the perlite i buy at home depot is too small of a particle, where do you find the larger ones?
 
the perlite i buy at home depot is too small of a particle, where do you find the larger ones?
I buy coarse perlite by the 4 cu ft bag at Southern States which is a long established chain of farm stores in my area. When I was making hypertufa, I bought it several years ago at another farm store as well.
Have you checked Amazon?
 
hmm ..... I did some research, I thought perlite was just pieces of Styrofoam mixed in the soil for aeration, found out its volcanic glass popped like popcorn
 
found this


seems better, bigger particles
Looks like a good product and it might be a bit coarser than mine but you really have to have them side by side to compare. I paid about half as much for mine.
 
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