· Gardenality.com's Answer
· You might have some success with overwintering certain varieties of annual plants indoors, however, keep in mind that you may have to transplant them into larger containers if you intend on using them in your landscape for another full season. Otherwise, they may become "root bound" and not perform well. This is particularly the case with Boston ferns grown in hanging baskets.
Best thing to do is remove the plant from the container and cut the root ball in two or three sections. Then cut foliage back and replant one of the sections in the hanging basket, adding some fresh professional potting mix to fill the container.
You could then use the other sections to make new hanging baskets. Same goes for many other annual plants when attempting to overwinter them indoors for use outdoors next year. Keep in mind that you will also have to provide adequate light to annual plants you are attemtoing to overwinter indoors.)