FlytrapCare Carnivorous Plant Forums

Hi,

Can crushed recycled glass (sold as an abrasive for sandblasting such as https://www.escablast.com/crushed-glass/) be used as a silica sand alternative when making carnivorous plant soil mix? Would possible trace amounts of other elements (such as to tint the source glass) be an issue? Has anyone done this?

Where do you get your sources of silica sand for soil media?

Not too sure about crushed recycled glass but, a lot of people use pool filter sand which is usually #20 quartz Silica Sand but, #20 is pretty fine sand. Most recommend a #12 coarse silica sand which can be hard to find depending on how much you need and where you live. - Sand is cheap but, expensive to ship - can be found on ebay & amazon. Horticultural perlite is a good but not perfect alternative to silica sand.

It should be perfectly fine to use. I have a couple of friends that have used crushed glass in their CP mix and saw no I’ll effects and had good results.

I used to use crushed glass as sand, and another local grower here has for years. Glass is completely inert so it's fine, though it will likely need to be rinsed before use. I have personally used crushed glass sold as both pool filter sand and as blasting sand - the pool filter sand seemed to have a chemical treatment that causes water to foam, while the blasting sand was less uniform, contained bits of plastic (also inert so not an issue) and smelled faintly of beer.

Sure, give it a shot. VFT's like a light, airy soil mix and adding something like crushed glass or perlite helps to prevent peat from compacting down.

Please note that crushed sand will add more weight to the soil mix than perlite which may not be an issue for you but can be in some situations.

Also, you might want to look into using paver base (NOT paver sand) as an alternative to crushed glass or silica sand. It's typically much more available and approximately the right size. As with all sand, you'd want to test it for salt, calcium, etc. to make sure it's fully inert but it might be a decent source for you.

Personally, I prefer dead sphagnum moss with perlite added in equal volume as the media of choice for vft's and prefer sphagnum moss over peat in general since it seems to produce the best growth. I did a small test last season between sphagnum and peat and the plants in sphagnum grew noticeably better.

This year I'm trying to grow out a bunch of plants so I can sell them in the NC State Fair in the fall and in that case, sphagnum is too expensive to use. Maybe I'll do a test between peat:perlite and peat:sand to see if it makes that much difference.

Anyways, hope that helps.

nimbulan wrote: ↑Tue Apr 18, 2023 3:01 am I used to use crushed glass as sand, and another local grower here has for years. Glass is completely inert so it's fine, though it will likely need to be rinsed before use. I have personally used crushed glass sold as both pool filter sand and as blasting sand - the pool filter sand seemed to have a chemical treatment that causes water to foam, while the blasting sand was less uniform, contained bits of plastic (also inert so not an issue) and smelled faintly of beer.

How course is this stuff? I've got some pool filter sand, and it's about as course as table sugar. In my neck of the woods finding a fairly course, inexpensive, and nonreactive sand is quite a challenge.

Huntsmanshorn wrote:

nimbulan wrote: ↑Tue Apr 18, 2023 3:01 am I used to use crushed glass as sand, and another local grower here has for years. Glass is completely inert so it's fine, though it will likely need to be rinsed before use. I have personally used crushed glass sold as both pool filter sand and as blasting sand - the pool filter sand seemed to have a chemical treatment that causes water to foam, while the blasting sand was less uniform, contained bits of plastic (also inert so not an issue) and smelled faintly of beer.

How course is this stuff? I've got some pool filter sand, and it's about as course as table sugar. In my neck of the woods finding a fairly course, inexpensive, and nonreactive sand is quite a challenge.

The pool filter glass was the same as every other pool filter sand - fairly fine but uniform since the filters need a specific particle size to work properly. The blasting glass was a fair bit larger, but with quite irregular and often angular shapes. They weren't sharp though and it was safe to handle.

I definitely understand your difficulty finding good sand. Here on the west coast coarse silica sand basically doesn't exist and it took me years to find some good stuff. And of course soon after I found out the mine was shutting down so I stocked up big time. I hope I never run out.

So this means I take clear glass jars and bottles, then crush them into sand and then use it in mixed substrates for CPs? Won’t the glass leach any minerals. Because it’s not the same as silica sand.

Barlapipas 6 wrote:So this means I take clear glass jars and bottles, then crush them into sand and then use it in mixed substrates for CPs? Won’t the glass leach any minerals. Because it’s not the same as silica sand.

Now that's how you end up with lots of sharp particles that will easily cut you when you handle it. I would not attempt making your own crushed glass at home.

I have heard that breaking glass into sand or powder is dangerous especially if you inhale it. So were can you find crushed glass that is safe to handle?

Barlapipas 6 wrote:I have heard that breaking glass into sand or powder is dangerous especially if you inhale it. So were can you find crushed glass that is safe to handle?

It'll be available at the same places as regular sand, it's just less common. I found a particular pool supply store that had the glass here, and a sandblasting supply company that sells a variety of materials.

nimbulan wrote: ↑Wed Apr 19, 2023 4:36 am The pool filter glass was the same as every other pool filter sand - fairly fine but uniform since the filters need a specific particle size to work properly. The blasting glass was a fair bit larger, but with quite irregular and often angular shapes. They weren't sharp though and it was safe to handle.

I definitely understand your difficulty finding good sand. Here on the west coast coarse silica sand basically doesn't exist and it took me years to find some good stuff. And of course soon after I found out the mine was shutting down so I stocked up big time. I hope I never run out.

Thanks for the info. I'll have to keep my eyes peeled and give the "blasting glass" a try. Hope I can find some.