Dear Garden Problem Lady: What is A Weed?

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Common field speedwell

What is a weed? For gardeners, a weed is any plant that is in the wrong place. In a bed of pansies, a tulip is a weed. Plants that are not wanted in lawns, gardens or agriculture are generically called weeds. Weeds are incredibly tenacious and abundant even at the start of the growing season. You can see them all over Capitol Hill in tree boxes and at the edges of gardens and lawns.

What are some common early spring Capitol Hill weeds and how can they be removed?

Chickweed

Chickweed, purple deadnettle and common field speedwell are winter annuals emerging in late winter, taking advantage of the lack of competition at this time of year. The seeds germinate in the fall, live through the winter and produce seed in the spring. When the weather heats up, they will die back, waiting for cooler days to reemerge.

Chickweed, Stellaria media, is one of the first spring weeds. A member of the carnation family, chickweed leaves are football-shaped and ½ to 1 ½ inches long, with tiny ¼ inch white star-shaped flowers with five petals that are deeply indented and appear as 10 petals. The flowers partially close in the evening and the leaves fold over new shoots and buds at night.

Chickweed reproduces from stem joints and seeds. One plant can create thousands through seeds and runners. The seeds are viable for up to 10 years.

Pulling chickweed out by hand works well in our small Capitol Hill yards. Be sure to get the roots and all of the plant. Take care in how you dispose of weeds, because they can still spread their seeds and regrow. Either eat them, put them in DC yard waste, which is composted at a high enough temperature to kill seeds, dispose of in the trash or give to chickens as a treat. The name chickweed reflects that chickens enjoy eating it.

Purple deadnettle, Lamium purpureum, has the square stem that identifies it as a member of the mint family, heart-shaped leaves with serrated edges, and light purple tubular flowers. The upper leaves have a purple or reddish tint. The common name “deadnettle” refers to the similarity in appearance to nettles, but this plant is not a nettle and has no sting.

Purple deadnettle

Purple deadnettle is an early food source for hungry pollinators and also self-pollinates, ensuring reproduction with or without assistance. Purple deadnettle has shallow roots and is easy to pull, especially when the soil is moist.

Common field speedwell, Veronica persica, has small, light-blue flowers (about 1/3 inch) and oval leaves with scalloped edges (1/3 to ¾ inch). Like chickweed, the stems are prostrate, growing along the ground, and the tips grow upright. Most growth occurs during the cool spring weather. Common field speedwell reproduces only by seed. An individual plant can produce up to 6,500 seeds that can remain viable in the soil for up to 30 years and also reproduces from nodes on existing plants and pieces of roots. With speedwell, it is especially important to remove all of the roots. Seeds require some light to germinate, so turning over the soil is helpful in preventing growth.

Want to learn more about gardening or spend time with people who like plants? Join the Capitol Hill Garden Club at their April meeting on Tuesday, April 9 at 6:30 pm at the Northeast Library, 330 Maryland Ave NE. Visit the club website at capitolhillgardenclub.org.

Gardening advice, information and commentary from the Capitol Hill Garden Club. Send your questions to capitolhillgardenclub@gmail.com