Q: I need to replace a tree in my small front yard. Can you tell me about the kousa dogwood? Santa Lavric, Duluth
A: Kousa dogwood is an excellent tree for urban landscapes. It grows 15 to 25 feet tall and has a bushier habit than the common Florida dogwood. It sports beautiful white (or pink) bracts in May, followed by glossy summer foliage and raspberry-like fruit in the fall. It can be planted in full sun; the root system is not intrusive. Several cultivars are available, including 'Milky Way,' 'Constellation' and 'Stellar Pink.' 'Wolf Eyes' has distinctive white leaf variegation but is best suited for shady landscapes. It would be hard to plant too many kousa dogwoods in metro Atlanta!
Q: Every year I have an invasion of boxelder bugs from the boxelder maples on the other side of my fence. Is there anything I can do to prevent them? John Jacquot, email
A: Like kudzu bugs and Asian ladybeetles, boxelder bugs instinctively congregate on house walls in the fall. Given a crack to crawl through, they overwinter in wall cavities and may find their way into your home. None are harmful to humans except for the aggravation factor. You can kill them with any garden insecticide as soon as you see them in late summer.
Q: I planted a Mexican heather the summer before last. After one growing season I cut it down and planted pansies around the remaining twigs. It returned this year and has grown to look like a low hedge. How can I save them again? Janice Page, Buckhead
A: It's not a common occurrence but Mexican heather has been known to occasionally survive winter cold in Atlanta. I don't have a reliable formula to keep them alive until next year. If we have a couple of days of severe cold your plants will not come back next spring.
Q: I am a chemistry student at Emory University. I enjoyed your website article about evaluating scientific claims. I would really like to know chemical and biological explanations for all the gardening information I see. Do you have suggested references? Marika Wieliczko, email
A: My training as a University of Georgia Extension agent gave me the scientific background to understand gardening but my experience as a 4-H club member gave me the skills to present science in an entertaining way. I can think of four good books for you: "Decoding Gardening Advice" and "The Truth About Garden Remedies" by Jeff Gillman, plus "The Informed Gardener" and "Sustainable Landscapes and Gardens" by Linda Chalker-Scott. Both authors use a science-based background to explain the hows and whys of gardening.
Q: With what should I spray my scheffleras to eliminate pests before I bring them in for the winter? Cathey Eves, DeKalb County
A: I once had a neighbor who would cover his houseplants with a paper sack and stick a lit cigar in the soil. He left it covered for only a few minutes. He said it "fumergated" his plants. They seemed to have no pests during the winter but they were a bit pungent for a few weeks afterward. I don't recommend you follow his example but you can examine the leaves of your plants for spider mites, mealy bugs and aphids. If found, spray outdoors with insecticidal soap or spinosad to control them.
