Hi there Teh Frog Whisperer, I think it depends on the plant. Some plants need soil and some don't. I have some in pots and some just in the sphagnum. When I do have the plants in pots I re-pot them up with sphagnum on the top and bottom of the new pot. It just separates the frog from the soil as allot of soils have growing agents and pesticides in. I hope this helps.