“Ask A Master Gardener” helps our readers to solve common problems concerning horticulture, gardening, and pest management through a trained and supervised staff of Extension Master Gardener volunteers. The Extension Master Gardener program is an educational program designed to enhance public education in consumer horticulture. Look for this weekly column on Fridays, as space permits.
Submit your questions by email to email@example.com. Or, you can call the local Extension Center at 252-641-7815 and tell them you have a question for a master gardener. You ask the questions and a local Master Gardener will return your call with a solution to your problem and share it with our readers.
Answers reflect research collected from land grant universities (NCSU or NCA&T) and through a national extension website, www.extension.org.
Q. Kathy P. (Tarboro) asks- I have an invasion of millipedes in the dirt in my yard. They are also in the dirt of all of my potted plants. They have even invaded my house. I would like to transplant hosta to my new house in New Bern and to my son's house in Baltimore, MD. Is there any way to move these hosta without taking the millipedes as those other locations do not have these stinky little critters? I certainly do not want to introduce them into yards that do not have them.
A. Controlling millipedes- The millipede species encountered by people most often is the common garden millipede (Oxidus gracilis). In late spring or early summer, homes are often invaded by these millipedes, possibly due to heavy rains and a rising water table which forces them out onto carports and driveways. The good news is that they usually do not survive more than a few days indoors unless a moist habitat and food source are available.
Millipedes prefer to live in moist areas with high humidity, such as under large rocks, wood piles, mulch and in turfgrass with excessive thatch. Their presence often goes undetected until a heavy rain causes them to migrate in large numbers. Millipedes are arthropods and play an important role in the cycling of nutrients in the soil. Arthropods that are active in the decomposition food web are called decomposers, detritivores, detritus feeders, microbivores, or saprophages. In addition to helping to break down organic matter, decomposers are often eaten by other arthropods, for example spiders, and can contribute to supporting populations of beneficial predatory arthropods.
Common garden millipede curled into a “C” shape.
Rachel Rowe, Clemson University
Chemical controls alone are not effective at reducing millipede populations. Follow these steps to reduce moisture in the landscape and deter millipedes.
De-thatch Lawns: Millipedes thrive in dense thatch layers.
Mow Lawns Closely: Keep lawns mowed at the recommended height to encourage quick drying after irrigation and heavy dew.
Remove Debris: Reduce wood debris, rocks, heavy mulch, leaf piles and firewood in the landscape. Because millipedes can inhabit compost piles, site piles further from the house. These areas provide a moist environment for millipedes.
Water Lawns in the Early Morning Hours: Irrigating a lawn in the early morning hours will allow it to dry more quickly.
Good Fitting Door Seals: Check the seal beneath all exterior doors for a tight fit.
Q. Bob F. (Tarboro) asks - How do you get rid of worms in a compost pile?
A. Don’t even think about it. Earth worms are beneficial, as they help decompose organic matter in compost piles and in soils. It isn't necessary to get rid of these worms in completed compost. In an active compost pile (turned regularly), the heat of decomposition will rid the pile of worms and other insect larvae mistaken for worms.
Q. Fran T. (Tarboro) asks: There are a lot of bugs in my garden! How do I know which ones are beneficial?
A: Not all insects are bad! Some of the positive things they do are to provide for production of fruits, seeds, and vegetables through their pollination services, and act as predators by eating some of the harmful insect pests. By eating dead bugs and vegetation, they help improve soil condition. They also can feed on weeds in the same ways they injure crops. Here is a list of some of our friendly bugs. Don't spray these-they are not our enemies!
• Dragonflies - they spend most of their time near ponds and the water garden and feed on mosquitos, their larvae, and other flying insects.
• Ladybugs - they feed on such bad insects as aphids, thrips, mites, scale, whiteflies, and mealy bugs.
• Fireflies - their larval offspring stalk the ground for slugs, snail, and soft-bodied caterpillars.
• Green Lacewing - they feed on aphids, mealy bugs, scale, thrips, and mites.
• Ground Beetle - they go after slugs, snail, and soft-bodied caterpillars. They are 1/4-1 inch long, irredescent bluish black in color and can be found under rocks, boards, and other garden debris.
• Praying Mantis - they feed on both beneficial and harmful insects,
• Paper Wasps - they paralyze harmful caterpillars with their stingers.
Q. Chris C. (Tarboro) asks - Why do my tomato fruits have dark, circular spots on them?
A. Tomato fruit with dark, circular, sunken spots are showing symptoms of anthracnose, caused by several species of the fungus Colletotrichum. Early symptoms appear on a ripened fruit as small, slightly sunken, water-soaked, circular spots. The lesions increase in size, become more depressed, and the central portion darkens. The fungus can infect both green and red fruit, and it can penetrate the skin of uninjured fruit. When green fruit are infected, it does not show spotting until it begins to ripen. Tomato fruit become increasingly susceptible as they approach maturity. Warm, wet weather promotes disease development. Splashing water in the form of rain or overhead irrigation favors the spread of the disease.
Treatment: Remove and destroy infected fruit. Rotate plantings in your vegetable garden. Weed control is important because the pathogen (fungus) has a broad host range that includes many common weeds. Regular fungicide applications can help prevent infections. Fungicide applications should begin when fruit are formed on the first cluster. Visit your garden center or contact the local Extension office for fungicide recommendations.
Q. Nancy H. (Tarboro) asks- How often should I divide my perennials?
A. Division of perennials may be necessary when the side shoots or runners become crowded by other plants. Aggressive varieties, such as Shasta daisy, Oriental poppy and aster, often need dividing every three years. Others can go longer before division is necessary. Spring and early-summer blooming perennials, such as peonies and poppies, are usually divided in the fall or when foliage dies (mid-September through mid-October). Plants that flower in mid- to late summer and fall, such as chrysanthemums and asters, should be divided in the spring before growth begins. Iris and daylilies usually are divided immediately after flowering.
“Ask A Master Gardener” also wants to include your “tried and true” gardening tips and techniques and snapshots from your garden; please share in an email to firstname.lastname@example.org or by writing to “Ask A Master Gardener”, c/o The Daily Southerner, P.O. Box 1199, Tarboro, NC 27886.