I live in Ontario and not much is readily available, except for limestone, and most important CHEAP to find. I have some red lava rock that I got from a bonsai guy but it is all 1/4". I would like much smaller, with some 1/4". Again, not easy to find. There is black and red but it is large. Mostly used as decorative stone in gardens and walkways.RAYWOODBRIDGE wrote:Don't know which part of Canada you live in ,but Lava rock 3-5mm grit would be fine
I find aquarium grit a bit to smooth for my liking. I do have some, though. Thank-youJaneO wrote:..There is quite a lot of aquarium grit which I have found agreeable, even if it needs washing first!
I do have some granite, I think? It comes as "Tubesand" in a long bag used as winter weight in a car/van trunk as added weight.ralphrmartin wrote:I use granite grit from the local quarry...
quartz! quartz! quartz! That is what I want. Again I can find it in large chunks used as decorative stone. It is way too much bother to crush it down and most of it powders anyway. Interesting that you would mention marble to stay away from. I tried some of the "Tubesand" which I thought was marble in vinegar this morning and there was no bubbling. uummm? I definately prefer sharp stones to smooth for a number of reasons.iann wrote:Granite, flint, quartz, its all pretty inert stuff. Usually depends what is available locally. Up here it is quartz. Just avoid limestone and all its variants, such as marble, chalk, or oyster shell. You can always test a small sample in vinegar, any noticeable fizzing is a bad sign...
Then make sure you choose a sharp grit. Smooth stones don't help drainage as much. Pick a size to suit your pot size, but probably 2-5mm in most cases.