Dig the holes a little deeper and wider than each section to plant to allow the roots room to grow, but don't plant them too low...loosen the soil and mound it up a little and plant them so that the level the actual leaf growth is at soil level. Mix a little compost in each hole. Don't use potting soil for anything but potting up plants. It actually doesn't contain any soil at all, and will eventually lose it's ability to store water. It's best to even remove as much of the potting soil you can when planting potted plants.