Hedysarum alpinum aka Sweet Broom

Hedysarum alpinum is a perennial of the pea family, Fabaceae. It lives for more than one year. People call it alpine chainpod or sweetvetch. It grows across northern North America and much of northern Asia. Its range reaches northern European Russia and parts of Kashmir, too. It is not native to Britain or Ireland. Wild plants grow among lime-rich rocks and in soils with gravel. In China, they also grow in wet meadows and swamps.

Plants reach about 3.3 feet (1 metre) tall. They spread to about 2 feet (0.6 metres) wide. A deep taproot makes well-rooted plants hard to divide. If this root suffers harm, plants may struggle to recover. Flowers appear in June, and seeds ripen in August. Each flower has both male and female organs. Insects pollinate the flowers, which give them nectar and pollen. These foods help native insects that pollinate plants through short northern summers.

Grow alpine chainpod in full sun; it cannot stand shade. It likes moist soil that drains well. It accepts sand, loam, and clay. The soil can be slightly acid, neutral, or slightly alkaline. Plants cope with short dry spells and soils with few nutrients. PFAF lists USDA hardiness zones 2–8 and UK zone 3. This UK zone is not an RHS H-rating. The plant fixes nitrogen, helping add it to poor soils. It can grow in garden beds and perennial food gardens.

Seed is the main way to raise new plants. Fresh seed tends to sprout more reliably than older seed. Scarify, or nick, the hard seed coat first. Then give the seeds several weeks of moist cold. These steps copy wear and cold in the wild. Plants may self-seed where nearby growth leaves enough space. The evidence says this spread is limited, not aggressive. The deep root makes division a less suitable choice.

Indigenous peoples across Alaska and Canada have long gathered the roots. They ate them raw or cooked, or dried them to store. The roots were a valued source of starch. Know the plant's identity before you gather it in the wild. PFAF cites safety reports that do not agree. These concern related plants, not just this species. Its own claims about root safety also conflict. This does not show that all plant parts are safe. Past root remedies included teas for coughs and sleep problems. People also used these teas for inflammation. These uses do not prove that the remedies work or are safe.