pdf | print

Pretty Girl holding ladybug

It seems Washington’s unseasonably cool, soggy spring gave many of our region’s pests a chance to breed. Suddenly, we have gone from very wet to pretty dry. Overnight, it seems, spider mites have spun their webs on yews and boxwoods. Working in our gardens has become nearly impossible due to the invasion of mosquitoes. Our beautiful gardens have been bugged. What’s a gardener to do?

Hill gardeners are not the kind of folks who sit back without a fight. We are take-charge types, and here are some friendly tips gathered from professionals and longtime residents to help combat this season’s insects and diseases.

Pesticides versus Organics
Pesticide use is a very emotional topic for most of us. Some gardeners feel that, used responsibly, pesticides are safe. They note that public agencies monitor for issues of concern. The most common pesticides are insecticides (to attack insects), fungicides (to treat diseased plants) and herbicides (to kill weeds). Faced with real health dangers – like West Nile virus, carried by mosquitoes – these gardeners feel that there’s a priority on speedy resolution of insect problems.

Frager’s Hardware (1115 Pennsylvania Ave. SE) and Ginkgo Gardens (911 11th St. SE) carry a variety of these products and have staff that can help you determine what might be best to use. But whether you fall into the zero-use or responsible-use camp on pesticides, there’s one thing we all can agree on: overuse is definitely a practice that should be avoided at all costs. Giving the weeds in your garden or alleyway an extra shot is needless, and in the long run, it harms beneficial plants and animals.

Organic gardening means the avoidance of synthetic chemicals like pesticides and relying more on natural methods to control the pests. The most effective method is to grow healthy plants in the first place, and many organic gardeners begin with the health of the soil. Regularly adding organic matter to your soil – like compost, leaf mold or well-aged manure – is going to give you a leg up. And choosing plants that help attract beneficial insects that will gobble up the bad bugs or attract birds and pollinators to the garden also helps a lot.

Some of the best plants for beneficial bugs are bachelor’s buttons, sweet alyssum, borage, anise hyssops, golden marguerite, fennel, cosmos, crown pinks, rue, yarrow, ornamental grasses and chrysanthemums. Walk around the Hill, and you will see our sunnier yards planted with a good variety of these plants.

Gather your Intelligence – The First Step in Debugging
After deciding which pest control approach best fits you, the next step is to properly identify the pests that are plaguing your garden and the plants that are playing host. This is often easier said than done. But, whether you are going to use beneficial insects to eat the bad ones or turn to pesticides, you have to know what is biting, eating or engulfing your plants.

In seeking advice, don’t bring the diseased or insect-riddled cutting with you to share.

A photo will do just fine. In doing my research for this article, I printed out a page of digital photos of the pest damage in my garden and took it with me on my visits. Jamie King at Ginkgo Gardens was happy to help me confirm my pest problems and, when in doubt, consulted a very large and detailed book to verify his hunches. Front desk staff at the US National Arboretum (3501 New York Ave. NE) did the same.

Websites through the Universities of Maryland, Virginia and DC also provide pages of information and post pest and disease alerts for our area. You aren’t alone. Between the US Botanic Garden and the US National Arboretum, we have some of the leading pest management experts around, and they can quickly identify the half-eaten leaf or mildew substance that has taken over your plant.

Buy Some Ladybugs
Aphids have been out in full force this summer. They are tiny insects that may be green, yellow, brown, red, gray or black. Some species have wings, and they attack a host of plants. Nasturtiums, roses, milkweed, chrysanthemums, tomatoes, peppers, carrots and geraniums seem to be highly susceptible. The good news is that spiders, pirate bugs, lacewings and ladybugs all are effective beneficial bugs that can be called into action to establish balance.

For over five years now, the Smithsonian’s National Museum of the American Indian (NMAI) has held ladybug release parties in July and August to introduce young folks to the benefits of ladybugs. Christine Price-Abelaw, head horticulturalist for NMAI, says the program is very popular with preschoolers and parents. “We invite the public to come and join us by putting the ladybugs on the plants to eat the aphids,” says Price-Abelaw. NMAI purchases the ladybugs online and stores them in their refrigerators until they are ready to use them. “It is amazing that in just two weeks time, the ladybugs have cleaned up our tomatoes, squash, corn and tobacco plants,” says Price-Abelaw. A typical bag of lady beetles (bugs) cost $13.95. “While some will fly off to your neighbor’s yard, most will stay put as long as there are aphids to eat,” she notes.

Keep an Eye on your Tomato Plants
Finally, news warnings about a devastating plant disease called Late Blight are very real. Late Blight is the same pathogen that caused the Irish Potato Famine and is known to spread like wildfire. It appears that the disease may have originated from tomato plants being shipped to the “big box” stores like Lowe’s, Home Depot, Wal-Mart and Kmart. The appearance of brown spots and lesions on a plant’s stems is the first sign. A soft rot collapses the stem and spots appear on the leaves. If your tomato plants develop these symptoms, you are advised to destroy the whole plant immediately. The Maryland Cooperative Extension Service has posted photos and information to help you at www.growit.umd.edu.
We should all remember to stay on top of bug problems for the benefit of our plants and our neighbors’ gardens. But the most important thing to remember is this: Don’t panic. There are many different approaches to tackling insects and bugs in our gardens and numerous local resources to call on.

For more information on Good and Bad Bugs, I refer you to Jessica Walliser’s “Good bug-Bad Bug Book: All you Need to Know About the Insects in Your Garden,” published by St. Lynn’s Press, 2008.