A: Rotenone has been used as an insecticide for more than 100 years and as a fish poison for more than 1,000 years. It is derived from the roots of tropical plants. These days, in order to balance the threat to fish in nearby streams with the need for organic insecticides, rotenone is usually mixed with pyrethrin, another organic insecticide. You should be able to find it locally and online from companies that specialize in organic gardening.
Q: My azalea had caterpillars clustered at the tip of the limb. Should I spray all plants, or just watch for caterpillars and then spray? — Dianne Dye, e-mail
A: Azalea caterpillar is an occasional autumn pest of azaleas. They defoliate random azalea limbs, but they will not kill the plant.
You can spray insecticide on them as you see them or simply wait for natural predators to kill them. Hornets and paper wasps find these caterpillars a delicacy.
Q: What would you recommend as a fast-growing ground cover in sunny and shady areas? — Glenn Moran, Monroe
A: For shade, I like Lenten rose or mondo grass. For sun, spreading juniper and purple euonymus are hard to beat. For more ground cover options, visit xrl.us/groundcover.
Listen to Walter Reeves from 6 to 10 Saturday mornings on AM 750 and now 95.5 FM News/Talk WSB. Go to www.yoursouthern garden.com for details on his TV show or visit his website, www.walterreeves.com.