It depends. If it is in raised bed no. I would definitely not recommend vermiculite for raised beds. It is mainly used to aerate soil in pots. In pots well yeah I would recommend.

I have three current beds 4x12. We put them in last summer after pulling out the small beds I had for three years. I never used vermiculite in any of my beds. I used peat moss, and composted manures from a nearby farm. The only compost I purchased was mushroom and it was cheap.
I've had excellent harvest with my beds even the past two years with the odd weather patterns in our area.

Good luck and have fun!

Necessary? Well,at least in my 2 short years of SF gardening experience I have discovered that raised beds with such light growing medium as composts and peat does not retain much moisture. Therefore this year I am mixing in some vermiculite to help retain some moisture so I don't have to water as frequently.

Ron

I find that it truly depends on the soil make up available. My best growing beds are my existing soil with my compost. They hold the moisture better than the Mel's mix. So I would say What soil do you have? Mel's Mix is surly better than any of the new suburban wasteland soil I have been around. I would do without the Pete moss, but that is a personal opinion based on my soil type and compaction problems.

Curt

the book says that in third world countries they teach the system using just compost, so........

My brother does not do SFG but does raised beds with a mixture of compost and topsoil. Very much a no-no for SFG purists, but he gets great results. He has said he does envy my mel's mix a bit, but is fine with his method. His is much cheaper. So the answer is no, you don't NEED vermiculite, but it is helpful if you can afford it.

Hi there. New to this forum but not new to Garden Web.

I did square foot gardening back in the early 80's and I'm pretty sure "Mel's Mix" didn't exist back then.

I had a wonderful garden =:)

I have used vermiculite and I have used clean sand. I use the same ratio. The sand works well although it is a little heavier to mix.

A local nursery advised against vermiculite due to his belief that there is no such thing as an asbestos-free product. But some web postings disagree. In any case, my soil produces well, but I will be adding vermiculite to help conserve water as it does flow a bit too easily through the soil despite my use of soaker hoses.