I love butterflies. I planted a butterfly bush. What do I plant next?
Butterfly bushes attract butterflies but cannot sustain a single native species. Surprisingly, to "grow" butterflies, the best plants are oak, willow and black cherry, followed by other native trees and shrubs including birch, maple, pine, walnut, blueberry, sassafras and spicebush. Top perennials are goldenrod, asters, sunflower, joe pye weed, morning glory, sedges and honeysuckle.
Every year ragged holes make my hostas an ugly mess, and I hate them. I used to sprinkle slug killer but it gets difficult when the hostas get thick and large. Help!
A safer alternative to the old slug killer is an iron phosphate product, which degrades as fertilizer and is less toxic to the environment -- important because beneficial insects and wildlife prey on slugs. You can also spread a sharp-edged material such as ground oyster shell (sold at farm supply stores as chicken grit). People swear by coffee grounds, egg shells, sweet gum balls, or even diatomaceous earth in plastic pipes that keep it dry. Lastly, dry out the area. Avoid frequent irrigation. Thinning your hostas will promote air circulation.
Spider mites thrive in hot, dry weather. Hose off foliage of plants they favor.
Ellen Nibali, horticulture consultant, works at Maryland Cooperative Extension's Home and Garden Information Center, and David Clement is the regional specialist. The center offers Maryland residents free gardening information. Call the center's "hotline" at 800-342-2507 (8 a.m.-1 p.m. Monday-Friday) or e-mail plant and pest questions through the Send a Question feature at hgic.umd.edu.