QUESTION: Can you suggest some flowers for a brick planter? It is under the eaves of my house on the west side but totally shaded. I've planted impatiens before but am hoping to find something that grows taller, 18 to 24 inches high, so they can be seen above the tall plants that are in front of this planter.ANSWER: This is a very challenging spot: hot but shaded; little rainfall to help you out with the watering. The impatiens you chose in the past were the sprawling type or short types bred for containers, hanging baskets and the front of shady flower beds.Since you need more vertical impatiens that will make a nice show behind your shrubs, I suggest looking for New Guinea impatiens. These are fine plants, and some, but not all, are capable of reaching 24 inches. However, they will require regular watering and good, well-drained soil.

QUESTION: I need information on whether I should continue to save two beautiful peppermint poinsettias that continue to survive. It has not dropped one leaf, and the blooms are as great as they were when I got them.ANSWER: What an impressive testimonial for poinsettias in spring. Normally, I tell gardeners to throw away their poinsettias about Feb. 1 and wait for the arrival of Valentine's Day flowers. This tends to produce letters in fall telling me how lovely the plants look after a summer outside and why did I tell people to throw away such a nice plant? And by the way, they ask, could you tell me how to make it bloom as well as it did straight out of the greenhouse last December?Your poinsettia must have been in a very sunny place all winter to have performed so well. It could go outside to a mild spot with morning sun where it will require lots of watering through the hot weeks ahead. Because the plant is in a pot, don't even think of putting it in afternoon sun. You would never stop watering it. Consider pruning it after the colorful bracts are done for the season. Otherwise, it will make a very big plant that may surprise you with its size.Give it some liquid houseplant fertilizer through the summer and bring it indoors before cool weather arrives. Starting in early October, a poinsettia requires 14 hours of uninterrupted darkness every night until about early December to initiate the flowers and colorful bracts.

QUESTION: I have seen a white wisteria growing. It is in danger of being cut down due to construction. I want to propagate this plant before it is lost. When can I harvest the seed?ANSWER: The flowers will form seed pods, but I don't think that is the best way for you to get a new plant. It typically takes many years for a seedling wisteria to bear flowers, and there is no assurance that they will be white. A softwood cutting taken off the new growth just before it begins to mature in early summer is a better method.Take a few small cuttings, 4 to 6 inches long, to root. Keep the cut end moist and plant them as soon as possible in a clean, sterile mixture formulated for seeds and cuttings. Cut off the leaves from the lower third to half of the cuttings first. Dip the cut ends of the wisteria in a rooting hormone powder before setting them in this mix.