Astragalus crassicarpus aka Ground Plum

Astragalus crassicarpus lives for more than two years. It belongs to the pea family, Fabaceae. People call it ground plum, buffalo pea, or buffalo bean. It grows wild in central and western North America. Its range takes in parts of Canada, the United States, and Mexico. It grows on prairies and plains, in fields, and beside roads. It also grows in rocky woodland gaps and glades. Bluff tops provide other sites where it grows.

Garden plants reach 0.25–1.5 feet (0.08–0.46 metres) tall. They spread 0.75–1.5 feet (0.23–0.46 metres) wide. A main root, or taproot, holds the plant in place. Above it sits a woody base with branches. Stems may lie on the ground or stand upright. The leaves are pinnate, with many pairs of small leaflets. These leaflets range from narrow to oval in shape. They have hairs on their lower sides. The low form suits open beds and rock gardens.

Flowers bloom from April through June, in spring or early summer. They form upright groups where leaves join the stems. Each bloom has the shape of a tube or bell. Flowers may be purple or pink-purple. Other blooms are cream or greenish yellow. Both blooms and fruit add interest to garden beds. The thick, fleshy pods look like small green plums. Unripe pods measure about an inch across. Butterflies visit the plant. It suits gardens grown for pollinators.

Grow ground plum in full sun and well-drained sandy loam. Soil can stay evenly moist or turn dry. The plant copes with drought and dry soil. It also grows in shallow, rocky ground. It is hardy in USDA zones 3–6. With the right soil, it needs little routine care. Its roots do not cope well when disturbed. Do not move plants once settled or split them. Use it in prairie plantings or native gardens. It also suits areas where plants grow as in the wild. Missouri Botanical Garden reports no major pest or disease concerns. Seeds can be slow to sprout and sprout at uneven times. Plants For A Future suggests sowing fresh seed in a cold frame.

You can eat unripe pods raw, cooked, or pickled. Reports describe a sweet taste, much like peas. Make sure you know which plant you have. Some related plants are highly poisonous. Missouri Botanical Garden says all other parts are poisonous. Edible pods do not mean the roots are safe. Plants For A Future records past use of root preparations as medicine. People used these to treat convulsions and bleeding wounds. That past use does not prove safe home use.