AV Soil Mix

Hi everyone. I have a quick question regarding the soil mix my AV's came in. I ordered from the Violet Barn and the soil seems to have little flakes in it. They look almost metallic. Does anyone know what that is? I'd like to make sure I'm getting the right mix when I take them out of their styrofoam cups and repot them. Thanks! Melissa

hiya,
Those are probably flakes of vermiculite. Some people (esp up north) like them, and others do not. Recently I was advised not to include more than 10% in the mix, but then lots of people have been growing plants in 33% vermiculite for years, so...... I would use whatever light mix you are used to using. A lot of people like to use commercial AV mix lightened with some extra perlite.

The little metallic flakes you refer to are vermiculite. It is a common additive to potting mixtures and soil... aiding in water retention and discouraging soil compaction.

Currently, my personal favorite mix for the gessies is one or two parts peat moss, one part perlite, and one part vermiculite.

BTW... welcome to the forum Melissa. There are alot of super-nice people here, that can help you with any questions or problems you may have. They've sure been good to me! And careful... gessies are addicting!!! ;*)

Karen

Hi Keyring... (we cross-posted!)

I figured she could get 30 different answers from 30 different people... not to say one is any better/worse than the next.

My question for you is... what was the reason for advising to limit the vermiculite???

it had something to do with cations or something *sigh*
I knew I should have paid better attention in physics, or is it chem or bio, LOL.

hold on.....


here is the little blurb in the writeup from our local chapter's newsletter. Our speaker was Bob Stewart from Mass. During the talk, he gave the 10% figure as a rough guide.

???

Better you than me!!!

No kidding. Basically, what I got from that part of the talk was don't use too much vermiculite :D

V is usually used to keep the soil light, and yet hold moisture. Seems like added perlite and maybe some water absorbent crystals would achieve the same result.
Also, if you wick, you wouldn't really need the V....

Actually, I think that says it is *good* to have some (not too much, a "sparing amount") of vermiculite in the mix. Instead of the phosphate in the fertilizer running right down out of the pot, some of the phosphate will attach to the vermiculite. The plant can then use that phosphate (a good thing), "taking it up at its leisure."

I think the reason not to use too much vermiculite is that it can hold too much water and make the soil too soggy. Some brands of vermiculite seem to be good for drainage (like perlite), while others have different particle size or something and hold way more water.

I never use vermiculite in wicking medium..............only 1/2 av soil-less mix and 1/2 perlite. I love to root leaves in 100% vermiculite as it works great for leaves of any plant and for av leaves.

Everyone has a different method..............I just stay away from vermiculite for a potting medium .......................when sowing seeds I like to put the "fine" vermiculite on top..............

Right, a sparing amount, meaning 10%, not 33%....

Yes, but it does sound like a little vermiculite in the mix would be a good thing because of its holding phosphate. I'd been avoiding vermiculite, using perlite and moisture crystals as you mentioned, but maybe I'll pick up a little bag of it...

it's interesting, as I thought the gist of that part of the talk was that it's better not to use it, but if you want to, then limit it to about 10%. I've had this Q since reading the write up - I suppose I could ask for clarification but I haven't bothered.... My mix automatically has a bit of vermiculite in it, but I stopped adding a lot more since I haven't been able to get my hands on a better grade. The stuff I have now is close to powder *ugh*. Powder+water=mush.

Well, the syntax on that quoted portion was certainly extra confusing! I think your impression is more likely to be the correct interpretation than trying to go by what the words logically (or not so logically) mean...

But I did think it was interesting that vermiculite would attract and hold phosphate in the mix. Is that really a good thing, do you suppose? A lot of folks seem to be finding that it's easy to over-fertilize AVs, so the vermiculite-phosphate thing might make over-fertilization even more likely... or not?

Thanks so much for the responses. I've been a little nervous about trying to make my own mix, so I purchased one online. I think I might try making my own mix next time I order some gesneriads. Which should be pretty soon, as they do seem to be a bit addictive. Just want to make sure I can keep the ones I have alive before I go and order more. ;o)