Q. Can I transplant several perennials growing in containers on my patio to my flower garden this fall?
A. Assuming the plants are hardy in your area, yes. Remove the plant from its container, score the roots with a sharp knife to prevent girdling and to encourage new growth, place the plant in a hole roughly the size of the container, cover with soil, and water. In areas with mild but freezing winters, you can cover the potted plants with a layer of mulch up to the tops of the containers. When the foliage dies back, pile some more mulch three- to-four inches above the tops of the containers, and water occasionally. When spring comes, you can remove the mulch and put the plants back on your patio.
Q. How do you transplant a really prickly cactus?
A. First, loosen the soil around the container with a knife. Then fold several sheets of newspaper lengthwise until the batch is about four inches wide. Wrap the newspaper snugly around the cactus, gripping the loose ends tightly. Lift the plant out of its container and place it in the new one, using a trowel to add additional potting soil, and a stick or dowel rod to pack it firmly.