Chickweed may sound like a 1970’s party girl, but the name actually refers to several common California winter weeds that can harbor pests and diseases.
There are three species of chickweed found in California and they all germinate quickly and in abundance, under the cool, moist conditions common to California winters. Chickweed can complete its lifecycle in as little as 5 weeks, with each plant producing 800 seeds. If a single chickweed plant goes to seed in your garden or landscape, it can take 8 years before the seeds of that first plant are no longer viable. Be on the lookout for chickweed seedlings from January through the end of March.
Native to Europe, common chickweed (Stellaria media) is now found in many regions of North America and Asia. Also known as winterweed and chickenwort, common chickweed has been used as food and herbal remedy, though there is little or no scientific research to back up claims of common chickweed’s ability to provide cooling relief. Many people find the taste of this somewhat succulent annual too bitter to enjoy. Common chickweed contains high levels of iron, but the bitterness is caused by saponins, which can be toxic in large quantities.
Common chickweed is differentiated from its non-edible cousins by fine hairs found only along one side of the stem, whereas other, non-edible chickweeds have hairs all around the stem.
Succulent leaves grow opposite one another, and have a pointed tip. Common chickweed can reach 4 - 6” in height, but it generally grows as a short, dense mat, especially in lawns. The roots are fibrous and found near the surface. Stems tend to be weak, and plants produce white flowers and seed capsules at the same time. Common chickweeds plants have 5-petalled flowers, but each petal is split, to create the appearance of 10 petals.
While grown as poultry feed and ground cover, common chickweed provides food and shelter for lygus bugs, thrips, pale-banded darts or spotted-sided cutworms (Agnorisma badinodis), and dusky cutworms (Agrotis venerabilis). Common chickweed can also carry cucumber mosaic virus and spotted tomato wilt virus.
Mouse-ear chickweed (Cerastium fontanum ssp. vulgare) is taller than other forms of chickweed, reaching 4 - 8”. Hairy leaves grow opposite each other in a star-shaped pattern. This weed grows horizontally by putting out roots wherever the stem, which tends to fall over, touches the ground. Flowers are tiny and white, with 5 petals. The fruit capsules are brown and somewhat crescent-shaped.
Removing chickweed is difficult. Under cool, wet conditions, chickweed plants may send out roots at the nodes, which means every tiny piece of chickweed is a potential new plant. Thick layers of mulch and hand weeding, preferably before plants go to flower, are really the only organic methods of control. Heavy infestations can be managed with soil solarization. Unless you are feeding these weeds to your chickens, it is better to get them off your property completely, to avoid reseeding.
Ploughing or rototilling the area can reduce chickweed germination, but you may simply be trading one problem for another, as other weed seeds are brought closer to the surface. Maintaining a thick, vigorous lawn is another way to reduce the number of chickweed seedlings that make it to adulthood. Allowing your lawn to be taller than a putting green can reduce the amount of sunlight that reaches chickweed seedlings.
Before you completely write off common chickweed as undesirable, you need to know that it is also one of the preferred foods of the rare dainty sulphur moth (Nathalis iole).
You can grow a surprising amount of food in your own yard. Ask me how!