Cirsium edule aka Edible Thistle

Cirsium edule, or edible thistle, is in the Asteraceae family. Its native range runs from Alaska south to Oregon. It includes British Columbia and Washington on the Pacific coast. It grows in the mountains, in a temperate climate. Records place it in wet meadows and open woods. These sites help explain why it needs moist ground.

This perennial can reach about 6.6 feet [2 metres] tall. Its life cycle is worth knowing before you plant. A plant may grow for several years before it blooms. Once it flowers, that plant dies. The term for this is monocarpic perennial. It does not form a clump that lives on. Those years of growth lead to just one bloom season. The evidence gives no mature width for plants in gardens.

Flowers appear from July to August. Seeds ripen from August to September. Each flower has both male and female organs. The species is self-fertile: it can set seed on its own. Insects also pollinate the flowers. Bees, flies and beetles visit, as do moths and butterflies. Its summer blooms thus have a place in planting for insects. Leave seeds to ripen to raise new plants from them.

Choose a sunny spot with moist, ordinary garden soil. Plants For A Future says it is easy to grow. It accepts sandy soil, loam and clay. It can grow in soil that is mildly acid or mildly alkaline. It accepts neutral soil too. The same source lists USDA hardiness zones 6–9. Its habitat suggests a place at a moist, open woodland edge. But the growing guide rules out shade, so keep that edge sunny. Sow seed where plants will grow, in early spring or autumn. At 68°F [20°C], seeds take about two to eight weeks to sprout.

You can eat several parts, but each needs its own prep. Cook the roots before you eat them. Peel young stems to eat raw; reports say they taste sweet. Pick young shoots in spring to eat raw or cooked. The roots may hold much inulin, which people cannot digest. This can ferment in the gut and cause gas. Plants For A Future lists no known hazards or medicinal uses. This does not prove safety for every person or pet. Its weed assessment does not flag the species as weedy.