Mona, I put them in soil. My soil in that area is improved - not the nasty clay I have naturally. I just make a little trough with the edge of a board, and put the seeds in then pinch the dirt over them. I do know someone who covers them with sand instead of soil, and he thinks they don't heave as much. I know someone else who puts digs a whole in the ground, inserts a coffee can with the top and bottom removed, or a plastic pot with bottom removed. They put the soil into the pot, and then put seeds, with one cross per container. This makes it easy for them to get all the little seedlings out and transplant a bit easier. I never tried that method because I thought all those babies roots all wound up together - I would not have the patience to untangle them.