Winter Weeds Don’t Hibernate in Landscapes
Happy New Year. Now get your gloves out.
A healthy expanse of turf grass is your best protection against the encroachment of winter weeds. But creep they will, because many grasses don’t actively grow in our Nashville winters, and left untended winter weeds will set seeds and create more of a problem the following year.
“Winter annual broadleaf weeds” is the official name for those bright green patches in an otherwise off-season lawn. Edges along planting beds, walkways, pavers and other landscape elements are particularly vulnerable because even a slight space between them and the grass in your landscape is an open invitation.
These are annual pests because the weeds complete their life cycle in 12 months. These weeds are not shy about reproduction; they produce seeds like crazy and those seeds will simply hang out in the soil under late summer, when they’ll germinate.
Winter weeds grow in the winter and flower in the spring, and controlling them while they grow but before they flower is the most effective non-herbicide approach.
Winter weeds to watch
By control we mean ripping them out with as much of the root as possible. But control starts with identification. With the help of the Turfgrass Science Department at the University of Tennessee Institute of Agriculture, we’ve put together some of the most common winter annual broadleaf weeds in Middle Tennessee.
Common chickweed (left) (Stellaria media)
Shiny leaves, vertical hairs along stem. Shallow roots, found in wet, shady areas
Henbit (right)(Lamium amplexicaule)
Square stem, often purplish, with hairy, kidney-shaped leaves. Purple flowers arranged in whorls, or concentric circles. Among winter weeds, Henbit is amazingly prolific.
Purple deadnettle (left) (Lamium purpureum)
Similar to Henbit, but leaves are attached to stem with petioles, or small stalks.
Shepherd’s purse (righ)(Capsella bursa-pastoris)
Deeply lobed leaves in rosette formation, produces a heart-shaped, triangular “fruit” in the spring. Often confused with common dandelion.
Corn Speedwell (Veronica arvensis)
Low-growing, with rounded, toothed lower leaves and smaller, pointed upper leaves.
And special thanks to the UT Institute of Agriculture for allowing us to use their images.
Strong grass weakens winter weeds
The weaker and less dense the turfgrass, the stronger the conditions for these winter weeds to take hold. Overseeding with cool-season grasses creates diversity, density and more protection against invasion.
We’ve identified five common winter broadleaf weeds in Tennessee; but weeds, alas, are not limited to winter or to broadleaf types. UT’s Institute of Agriculture, which has a turfgrass department that works with people and companies in our industry, put together an interactive weed identification chart with photos and details of 42 grassy weeds and 65 broadleaf weeds. Each entry has multiple images that shows weeds in various growth stages, making identification easier before and after flowering.
If your lawn is looking greener than it should in January, you also can give us a call. The weeds aren’t the only ones who work in the winter.