Many of the mustard family plants are similar, but the group itself is fairly easy to identify. Here are the most prominent characteristics in common:
Vegetables such as broccoli, kale, cabbage, and cauliflower belong to this family, all sharing the pungent taste that reaches its peak with horseradish root. Many of the wild mustards have edible leaves (when young), as well as edible flowers, seeds, and/or roots. Mustards are high in calcium, potassium, and B vitamins, as well as cancer-preventing substances.
A common wild mustard is wintercress, which is knee-high when it blooms in spring, with brilliant yellow flowers. The leaves have a spade-shaped terminal leaflet with irregular smaller leaflets along the leaf stem, similar in shape to those of watercress and a number of other mustards. Wintercress leaves are delicious in salads when young, and the flower heads with associated leaves are tasty when stir-fried with garlic. Once the seeds begin to form, the leaves become extremely bitter. Some people find the plant too pungent to eat, but it is sweetest and mildest in winter, when it stays green even under the snow. It thrives in a variety of habitats, from lawns and fields to the banks of streams.
Garlic mustard blooms early in spring. Its small white flowers and wavy-edged leaves are abundant in open woods. The garlicky flavor makes the leaves and flowers excellent in salad or pesto. In midsummer, the seeds can be shaken out of the long pods and sprinkled on food as a condiment. The leaves are at their best in late fall through spring and, like those of wintercress, remain green in winter. The roots of garlic mustard may be chopped and put into a blender with vinegar to create a horseradish-like condiment.
Dame’s rocket is another spring-blooming mustard, often mistaken for phlox because of the tubular flower bases. Phlox, however, has five petals. The four-petalled dame’s rocket flowers vary from white to a deep pinkish-purple and are prominent along the roadsides. The leaves are too pungent to be edible.
Shepherd’s purse leaves are delicious in early spring, when they pop up from the ground in basal rosettes resembling those of young dandelion greens. After the plant puts up a flower stalk, the basal leaves disappear and are replaced by small, stringy leaves. By June, the heart-shaped seed pods have formed. Wild food expert Steve Brill says the seeds have sticky surfaces that trap minuscule insects, which are digested and assimilated by the baby plant, enabling it to grow in poor soil.
Other wild mustards include poor-man’s-pepper, watercress, tower mustard, toothwort, field pennycress, and many more.
For more information on learning plant families as an aid to plant identification, see The Rose Family and The Mint Family