Jeffersonia is a genus of flowering plants with just two species, found in Asia and North America. Members of this genus are relatively rare in both native ranges and in some regions are treated as protected plants. They have been used historically in traditional medicine, although the plants also have some toxic properties and must be used with care in herbal medicine. Gardeners may cultivate them as ornamentals and they can be aesthetically pleasing in massed plantings with other wildflowers.
Members of this genus are known as rheumatism root, referencing one historic medicinal use, or twinleaf, an apt descriptor for a plant with leaves that look like pairs of leaves stuck together. The flowers are white and have eight petals, rising on long, slender stalks directly from the base of the plant. Jeffersonia is a perennial genus and will spread in clumping masses over time when it is in an environment it likes. The flowers develop into thick, fleshy pods with small seeds inside.
In nature, Jeffersonia species prefer soils with a high lime content and gravitate towards woodlands. They need shade or filtered sunlight to survive and thrive on soil with a high percentage of organic matter, such as leaf litter. These members of the barberry family can tolerate a range of conditions from relatively hot, humid summers like those experienced in the American South to cold winters with snow in regions like the Appalachians.
Medicinal uses for J. diphylla, found in North America, and J. dubia, the Asian species, are similar. Both plants historically have been used to treat stomach and joint complaints, and Native Americans utilized the plant in a topical poultice. The root appears to contain compounds that can be of use in fighting tumors, and it is possible the plant was used in the treatment of cancers as well. One problem with herbal medicines is the irregularity of dosages, which makes it challenging for even experienced herbalists to use potentially toxic plants safely.
Gardeners interested in cultivating this plant can find seeds or seedlings through catalogs and at some nurseries. It is advisable to avoid collecting plants in the wild, as many wild Jeffersonia populations are unstable and may be disturbed by collectors. Good companion plantings include bloodroots and trilliums, two other famous woodland wildflowers. Gardeners with mature Jeffersonia plants may want to make seeds or divisions available for trade or sale through gardening exchanges, as this will help reduce reliance on wild plant populations.