Store bought soil can have all sorts of weird things in it. You'd be taking a risk. I wouldn't do it. I just cut the grass and feed it out. The grass will re-grow many times that way if you keep it watered and in a sunny window sill.Thank you. Can I get some organic? Soil and put it in the pot and put the seeds in there with that cause I bought 4 of these kits, and I kind of want to put the whole thing in there and let him eat it when he wants.