I bought sponges from Henry field's a few years ago.. loved the little kit .. then they changed the sponges.. and I don't like them anymore.. it was a simple six pack in a plastic container.. was so nice if you just wanted to start a few seeds rather then a whole flat.. and I found if I plant the sponges in the ground in spring.. the critters would run over it.. feel something different and dig them up.. after a few weeks of replanting the seedlings every day.. I just gave up.. but the new ones were too soft and would collapse easily
