Am a little stumped on this one.
Vermiculite (heated up mica) retains water and some nutrient and promotes aeration and soil drainage/lightness
Perlite (different version of heated up mica) retains water but not nutrient and promotes aeration and soil drainage/lightness
Sand (many different kinds form course "builders sand" with variable grain to very fine spherical grains) No nutrient value and provides aeration and drainage.
Need to generate about 80 gallons of container mix/soil (possibly yearly)
What are the pros and cons of each.?
Which is better for what and why?
What's the best bang for the buck?
I feel like I missed something when I was researching,
Jit when I was flirting with growing out trees to live in pots. and lived in new england the hands down bargain was granite grit (the finest size). AKA road grit. In past years it went as cheap as $ 5.00 per ton (if I picked it up). And about $10 a ton for bark mulch from saw mills.
By measure I used one part of sifted bark mulch, and one part sifted granite grit.
This ment I picked it up and sifted each,
Heat expanded shale was in use at some cinder-block mills and was pricier (about $80 a ton).
You have not said what your end-use is, so I substituted mine. Hope this helps.
I wanted the fastest draining soil I could fabricate. Water went through this like corn through a goose.
By measure I used one part of sifted bark mulch, and one part sifted granite grit.
This ment I picked it up and sifted each,
Heat expanded shale was in use at some cinder-block mills and was pricier (about $80 a ton).
You have not said what your end-use is, so I substituted mine. Hope this helps.
I wanted the fastest draining soil I could fabricate. Water went through this like corn through a goose.
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applestar
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Some relevant answers --
I don't like vermiculite nor perlite for different reasons. Primarily because they are mined. But they have their uses.
I'm old enough to be influenced by memories and negative opinions due to asbestos in vermiculite mined from specific regions. Of course this is no longer the case and the industry is on the alert for that sort of thing, though I suspect there must be some kind of minimum allowable. I feel that Vermiculite is also lousy in large containers and in-ground use because they are puffed layers of mica and just as easily compress back into flat mica flakes. I have accepted their usefulness in some instances for seed starting.
Perlite -- perlite dust is crystalline and can seriously choke you if inhaled. I always hold my breath and change clothes after using. (Not a fan of masks) It is useless in tiny grain sizes but are available in large and extra-large large grain size, in bulk size bags for surprisingly reasonable cost, most likely because they are mostly air and light, saving freight costs by weight. Really silly to buy in tiny expensive bags, IMHO. Very useful when you need lightweight mix. Useless when you need heavy mix that can help weigh down the container and not allow tall/big plants to fall over with any excuse for a breeze. Perlite pockets can provide homes for good microbes. I hate that perlite inevitably work their way out of the soil mix because they float and eventually get washed out.
Sand - horticulturally, recommended sand is builder's sand, sharp sand. Soft, rounded (beach, river delta) sand is not as well draining. You don't want to use salty sand. Most recommend all-purpose sand, but source may be variable. Paver sand and gravel-mixed underlayment sand is another choice. But I still sometimes get play sand because some of those are washed and sterilized. But don't get the scented ones (Yes I found out there is such a thing
) I also like to get white play sand for the color effect sometimes when using as top layer/mulch.
Large-grain (not powdered and definitely not heat-treated pool filter )diatomaceous earth, sometimes sold as oil absorbent in auto stores is another one I sometimes use. I like the perlite/aquarium gravel sized one. Last time, I ended up getting sand-sized one. One time I opened a bag of oil absorber only to discover it was clay, not heated so it dissolved into soggy lumps that would do nothing for drainage, actually made it worse. Auto store accepted return of opened taped closed bag with no arguments, tough.
I used to be able to go to a farm supply store next town over. Now it's gone and it's harder to get chicken grit. One time bought ground oyster shells. That worked well, too. I believe these add calcium and also could raise pH.
I don't like vermiculite nor perlite for different reasons. Primarily because they are mined. But they have their uses.
I'm old enough to be influenced by memories and negative opinions due to asbestos in vermiculite mined from specific regions. Of course this is no longer the case and the industry is on the alert for that sort of thing, though I suspect there must be some kind of minimum allowable. I feel that Vermiculite is also lousy in large containers and in-ground use because they are puffed layers of mica and just as easily compress back into flat mica flakes. I have accepted their usefulness in some instances for seed starting.
Perlite -- perlite dust is crystalline and can seriously choke you if inhaled. I always hold my breath and change clothes after using. (Not a fan of masks) It is useless in tiny grain sizes but are available in large and extra-large large grain size, in bulk size bags for surprisingly reasonable cost, most likely because they are mostly air and light, saving freight costs by weight. Really silly to buy in tiny expensive bags, IMHO. Very useful when you need lightweight mix. Useless when you need heavy mix that can help weigh down the container and not allow tall/big plants to fall over with any excuse for a breeze. Perlite pockets can provide homes for good microbes. I hate that perlite inevitably work their way out of the soil mix because they float and eventually get washed out.
Sand - horticulturally, recommended sand is builder's sand, sharp sand. Soft, rounded (beach, river delta) sand is not as well draining. You don't want to use salty sand. Most recommend all-purpose sand, but source may be variable. Paver sand and gravel-mixed underlayment sand is another choice. But I still sometimes get play sand because some of those are washed and sterilized. But don't get the scented ones (Yes I found out there is such a thing
) I also like to get white play sand for the color effect sometimes when using as top layer/mulch. Large-grain (not powdered and definitely not heat-treated pool filter )diatomaceous earth, sometimes sold as oil absorbent in auto stores is another one I sometimes use. I like the perlite/aquarium gravel sized one. Last time, I ended up getting sand-sized one. One time I opened a bag of oil absorber only to discover it was clay, not heated so it dissolved into soggy lumps that would do nothing for drainage, actually made it worse. Auto store accepted return of opened taped closed bag with no arguments, tough.
I used to be able to go to a farm supply store next town over. Now it's gone and it's harder to get chicken grit. One time bought ground oyster shells. That worked well, too. I believe these add calcium and also could raise pH.
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ID jit
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tomc,
Am trying to grow strawberries in container, I think, SIP's (not completely sure what I just finished building. Picking materials up by the ton isn't going to work so well with a highly modified 92GTI. Am looking to keep the soil/mix as wet as I can and just short a root rot and fungi breeding ground. "Road grit" sounds interesting though, but bark mulch in bags I don't trust - killed an entire flower garden with it once at just 1 to 1 1/2 inches deep and I did not cover the plants.
applestar,
Thanks for the heads up mica variants. You have been very helpful with all of this. The more I learn the harder it is to figure out. Half considering just going with 1/3 builders sand and 2/3 mulchy compost at this point or a 50/50 mix of garden soil and sifted compost. Garden soil I have is a base of fine, green/grey glacial till with a long history of organics being worked into it - black when moist and still drains too well. Garden is a bit overfull anyhow.
Am trying to grow strawberries in container, I think, SIP's (not completely sure what I just finished building. Picking materials up by the ton isn't going to work so well with a highly modified 92GTI. Am looking to keep the soil/mix as wet as I can and just short a root rot and fungi breeding ground. "Road grit" sounds interesting though, but bark mulch in bags I don't trust - killed an entire flower garden with it once at just 1 to 1 1/2 inches deep and I did not cover the plants.
applestar,
Thanks for the heads up mica variants. You have been very helpful with all of this. The more I learn the harder it is to figure out. Half considering just going with 1/3 builders sand and 2/3 mulchy compost at this point or a 50/50 mix of garden soil and sifted compost. Garden soil I have is a base of fine, green/grey glacial till with a long history of organics being worked into it - black when moist and still drains too well. Garden is a bit overfull anyhow.