Container Gardening, no Vermiculite

[lizallen]

I'm starting a container vegetable garden but I don't want to use vermiculite. My plan is potting soil and peat moss, do I need the vermiculite?

Also, do I have to buy a special organic potting soil to grow organic veggies or is that just a gimmick?

[lmonter]

Vermiculite helps lighten/aerate the soil, and can make your pots a little easier to lug around. Soil is heavy, dense, and can compact down to not let the plant roots do what they want. You can do without it, but to get your mix light/fluffy enough may leave you with pretty acidic soil.

That said, there is an alternative - perlite! I'm actually on the hunt for a bunch of perlite myself. A friend uses styrofoam peanuts in the bottom of her 5-15 gallon pots, but that idea squicks me out. Hence the perlite hunt.

I'm just going to do my own seed starting mix as usual - compost, peat moss and perlite until it's to the fluffiness I want (I don't measure, just throw stuff into the bucket and mix).
With my giant pots, I'm thinking I'll do a nice chunk of perlite, then some garden soil from my yard (I have a hefty garden outside but may be moving, so need to be ready to take things with me), topped off with a few inches of my seed starting mix to try and minimize weed germination.

[lizallen]

Thanks for the info on the perlite. I had read somewhere not to use it in containers but the site never said why or anything. I'm just not sold on how safe vermiculite is supposed to be.

Normally I just mix a few bags of top soil, peat moss and maybe some animal manure with the garden but, we moved so everything will be in pots now. I can't grab dirt from the earth or anything either... unless I did up the grass in front of our rental and I don't think anyone would like that!

So, just peat moss won't do the trick? I have to use perlite or vermiculite? Are those organic or do they fall in line with organic gardening?

[lmonter]

Perlite is just rock popcorn - puffed lava rock or something if I vaguely remember right. Vermiculite is the one with all the health issues.

Well, if everything in my pots tanks I'll blame it on the perlite. I think it is in soil mixes like Black Gold Seedling Mix though...

You could always see if you could grab some dirt from a neighbor or local friend or whatnot to mix in. Just peat moss would make me wary, unless you're only planting pine trees or blueberries (or lilacs). You'd have to test the acidity of the soil to see whether you'd be comfortable with just peat moss. Or there's something like cocopeat - shredded coconut husk fibers. That might not mess around with pH as much, but could also be a little pricey.

I'm not as fussy as others about the whole organic label. If I know how/where things are grown and such, having the official USDA label is very much not an issue for me. If I can feel comfortable sending my kids out to my yard or whatever u-pick operation we're at and not worry about them snacking on whatever, I call it good. But it does mean I still don't want to use styrofoam peanuts in my growing containers.

[DashsMama]

From astdr.cdc.gov

Vermiculite Garden Products
Is there asbestos in the vermiculite sold for gardening uses?

Not all vermiculite garden products contain asbestos, but an EPA study showed that some contain low levels of asbestos. Asbestos was found primarily in the unmixed vermiculite product sold separately as a soil amendment. However, some was found in premixed potting soils. Because the Libby mine closed in 1990, newer products are not expected to contain significant amounts of asbestos. It is possible, however, that some older products could still be on store shelves.

What precautions should I take?

Although the health risk to home gardeners is low, the following precautions are suggested:

* Use premixed potting soil because it contains more moisture and less vermiculite and therefore reduces the amount of dust that might contain asbestos.
* Keep vermiculite moist while using it to minimize dust and the possibility of releasing asbestos fibers into the air.
* Handle the material outdoors or in a well-ventilated area.
* Avoid bringing dust into the house on clothing or shoes.
* Try alternatives to vermiculite, such as peat moss, sawdust, perlite, or bark.

I remember reading that it is important to lighten up the soil in containers for both your back health and the plants' overall health. Peat will do that but also add acid to the soil that you will need to counteract with lime. I don't know if you care about this, but peat is also not not a sustainable product (we are harvesting faster than it can regenerate) so many people avoid using peat for that reason. If you are mixing your own potting soil and want to avoid vermiculite, perlite should be a healthy and effective substitution.