If you use potting soil and a container with drainage holes you can place the plants on top of the soil than cover the roots with additional soil. Just make sure you loosen the soil already in the pot first so the roots can reach down into the potting soil. I like to firm the soil on top of the roots gently with the palm of my hand and then water to settle the soil. If any roots are still showing after you water add a bit more soil to cover them. Keep growing, Marianne Binetti