Been doing it for years, it's called soil blocks. Much better system than all those plastic pots.

Here is a link that might be useful: soil blocks

bi11me - I looked at the video that you linked to - dont they fall apart fairly easily? I can just imagine letting them getting a bit to dry and coming in to find loose piles of dirt, and wouldnt bottom watering just melt them all?

I bought a case of 4" "cowpots" to use this year which should allow air pruning of the roots. they were about .30 each, so a little pricey. I like the idea of just using soil, but I cant visualize them holding up for 4-10 weeks.

They last fine. The mix is pretty sticky and fibrous, sort of like dirty papier mache. Ideally they are watered by capillary action - they sit in a cloth that wicks water from a reservoir, but they can be misted easily, or with a fine rose watering can. It is also not hard to make the mix yourself, if you need a lot. There are several recipes published. If you use a reservoir set up, there is very little labor involved.

Interesting. I do wonder about the fibrous nature of fast-growing veggie roots and the root hairs being torn from the root trapper fabric as the seedlings are potted up. Perhaps okay for trees, but not all veggies?

Using paper cups gives you a slick inner surface that peels away from the roots without damaging them too much. With soil blocks you get just a little natural root pruning when potting up, but the seedlings seem to like it.

Planatus,

Good point, and I don't know the answer. I would plan on using this company's plastic seedling trays, which are big enough to grow the plant until moving it to a 10-gallon RootTrapper container to grow for the rest of the season..

I bought some trees and shrubs from a local nursery and I was impressed with their root systems, having been grown in these containers. But no one can offer much experience with veggies. I started thinking about it when I started those tomatoes in cups and only two weeks later they were rootbound. That really surprised me!

Rosefool