Moths have ruined all the wool clothes in my closet. They aren't the kind that fly around lights at night. They're tiny, and sometimes I only see larvae. I used a trap, which killed some. I also tried cedar balls, blocks and hangers. I bought a bomb, too, but it's so toxic I'm afraid to use it. I saw a commercial for something that plugs into an outlet and sends out a frequency to drive them away. What should I do next?

Using mothballs and cedar are preventive measures against clothes moths. A different set of measures must be taken to control an active infestation.

The tiny adult moths mate and die — it is the larvae (small white caterpillars) that do the feeding damage. Their primary food source is soiled woolens. "Soiled" is the operative word here. First, empty the closet and dry-clean any salvageable woolens. Dry-cleaning kills all stages of clothes moth. Hand-washing is also helpful. Vacuum the closet thoroughly, concentrating on areas where larvae hide, such as baseboards, cracks in floors, shelves, etc. Store cleaned woolens in sealed containers.

Cedar blocks can be used for added protection. Use mothballs or flakes containing naphthalene as a last resort (avoid those with paradichlorobenzene, or PDB) and only in sealed containers. Using bombs or the sonar device you mentioned is not recommended.

Read our publication HG 60: Fabric Pests on our website. Contact us by phone or email if your clothes moth problem persists.

Are nandina berries okay to use in outdoor wreaths? Someone told me they are invasive. I love the bright red clumps of berries, and a friend has been letting me use hers for years.

Nandina shrubs are tough and adaptable, as well as beautiful and pest-free. They even tolerate dry shade, one of the most difficult gardening challenges. In the Southeast U.S., particularly Florida, this Asian shrub has become truly invasive. However, in Maryland it has not proved to be a danger to natural areas.

Seedlings may appear under nandinas, but they don't spread far or grow aggressively or crowd out native plants. So enjoy them. After the holidays, just don't throw the berries into a wild area.

University of Maryland Extension's Home and Garden Information Center offers free gardening and pest information. Call 800-342-2507 or send a question from the website at hgic.umd.edu.

Plant of the week

Paperwhite Narcissus

Narcissus tazetta

Now that flower gardens are brown, create joy inside by forcing bulbs. Many bulbs can be tricked into blooming out of season, but the easiest are from climates without a cold period so artificial chilling is unnecessary for blooming.

Paperwhite narcissus bloom happily in almost any nondraining container. Fill the container with pebbles, coarse sand, or light potting mix to 1 to 2 inches from the top. Set bulbs close together. To anchor, cover with pebbles to a quarter of bulb height. Add water to bulb bases. Keep cool in low light until they root and shoots begin. Then they can take direct sunlight until flowering starts. If they grow too tall, support with a thin stake and ribbon. Once blooming, move into lower light or wherever best enjoyed.

—Christine McComas