Cardamine is a diverse genus of flowering plants in the mustard family, Brassicaceae. There are more than 150 known species in this genus, taking a wide variety of forms and appearing in every region of the world except for Antarctica. Some species are cultivated ornamentally and are available from nurseries and garden supply stores. Others are viewed as invasive weeds and can become quite a nuisance in the garden because they are hardy and take to a wide variety of conditions.
Members of this genus can be annual or perennial, producing leaves in a basal rosette. A stalk typically develops and branches out as the plant matures. The leaves can vary in size and shape. At the tops of the stalks, small clusters of white flowers develop, eventually maturing into long seed pods. Like many plants that produce pods, Cardamine has developed pods designed to propagate the plant as effectively as possible by popping open and scattering the seeds once they are fully mature.
Some ornamental species have variegated foliage, unusually large flowers, and other features that make them visually interesting. They grow best in partial to full shade in moist gardens, and may spread out if they like the conditions where they are being grown. Cardamine species may be known with common names like shotweed, bittercress, pepperweed, and snapweed, all names to look for when searching for plants at the nursery.
Species more commonly identified as weeds tend to be smaller and more persistent than ornamental species, without the attractive physical qualities that make their cousins more visually interesting. These plants can be difficult to eradicate from the garden unless gardeners are highly attentive about weeding, as every time the seed pods pop open, they scatter seeds across the garden, ensuring that a new crop of weeds will set in. Using weed barriers can help prevent these plants from gaining a foothold.
Some Cardamine species have a history of use as medicinal or food plants. Medically, some species were used to treat gastrointestinal conditions, although research has not suggested that any species contain medically useful compounds. The name of this genus is a reference to relatives grown for use as spices, and species safe to eat do indeed have a sharp, peppery flavor. Other members of the mustard family are larger and thus are better choices for cultivation as food plants, and Cardamine is rarely seen grown as a source of food.