Hoary Bittercress Cardamine hirsuta

Hairy Bittercress is a winter annual broadleaf weed and is a member of the Brassicaceae or mustard family. Other common names include Bittercress, Flick Weed, Hoary Bittercress, Lamb's Cress, Land Cress, Shot Weed, and Springcress. The genus name, Cardamine, is Greek for "Kardamon," and translated means "cress." The species name, hirsuta, is Latin and means"hairy." This is about the tiny hairs on its leaves and stems.

The plant is native to Europe and Asia. It has been introduced in most of all other continents including North America, South America, Africa, and Australia. Hairy Bittercress is typically one of the first weeds to appear in spring. It may be seen in lawns, parks, gardens, and paved areas. It is capable of growing year-round when suitable environmental conditions are met. The seeds germinate in the fall or winter. Typically they are dormant in cold weather, and they resume their growth in the spring and produce more seeds. It has a 12-week lifecycle. They can quickly invade sparsely planted lawns or poorly mulched gardens. It is commonly found in sunny, damp, or disturbed soil.

The stems are erect, branched, and 3-10 inches tall. The root is fibrous and shallow. In the spring, clusters of tiny white flowers emerge that have cross-shaped petals on the ends of the stem. The small green leaves are mostly on the lower portion of the stem and form a flat rosette. Tiny hairs are on the upper and lower surfaces of the leaves. The fruits appear between March and May. They are siliquas or long narrow seed pods rods standing upright around the flower. When they mature, seeds are dispersed up to several feet from the plant. Each plant may produce 600 to 1000 seeds. 

The weed quickly becomes prolific in the garden and is best controlled by prevention. Hand weeding and adequate mulching of garden beds are helpful. Frequent mowing in the early spring removes flowers before seeds develop. Selecting the correct turf grasses that can develop a dense ground cover is important. Proper fertilizing, mowing, and watering will encourage lawn growth and reduce weed establishment.  If these measures fail, various pre-emergent or post-emergent herbicides may be used.

Hairy Bittercress flowers and leaves are edible and valuable nutrients. Although the name suggests that they may taste bitter, they actually have a mild peppery taste.  A few sprigs may be added to salads, salsas, and pesto. The flowers are tougher to chew. 

These plants are a food source for spring azure (Celatrina ladon) and falcate orange-tip caterpillars (Anthocharis midea). Hairy bittercress may also host aphids, whiteflies, and mites. Bumblebees are attracted to Hairy Bittercress for nectar and pollen. The weed attracts bees in the spring when other flowers are sparse.  Early butterflies are also attracted to the tiny flowers.