Welsh Onion

Welsh onion (Allium fistulosum) is a perennial bunching onion that forms clumps of upright, hollow, blue-green stems without developing a true bulb. It is widely used in Asian cooking and makes an excellent scallion substitute year-round. Hardy varieties survive Nordic winters outdoors, re-sprouting from established clumps each year. Plants grow 30–60 cm tall and thrive in full sun to partial shade.

Growing

Start seeds indoors 6 weeks before transplanting outdoors, sowing 1 cm deep at a soil temperature of at least 5 °C. Germination takes 10–20 days. Sow seeds in small groups of 2–5, spacing groups 5 cm apart in rows 20–40 cm apart. Direct sow outdoors once soil is workable and nights remain above 2 °C. Transplant seedlings outdoors once nights stay above 2 °C consistently.

Care

Water regularly to keep soil evenly moist but not waterlogged. Feed with a balanced liquid fertiliser every 3–4 weeks during active growth. Mound soil around stems (earth up) to extend the white shank length. Perennial varieties can be divided after the second year — separate clumps and replant individual shoots to renew the bed. Remove flower stalks on annual varieties to maintain leaf quality.

Harvest

Harvest from 65–70 days after sowing once stems are pencil-thick and upright. Cut individual stems at soil level with a sharp knife, leaving the rest of the clump to regrow — a true cut-and-come-again crop. Perennial varieties can be harvested from early re-growth through late autumn. The long white shank can be extended to 40–50 cm by earthing up before harvest.

In the kitchen

Use both the white shank and green tops raw in salads, salsas, and garnishes. Slice thinly for stir-fries, soups, ramen, and Asian noodle dishes. Grill or char whole stems as a side vegetable. The mild, aromatic flavour is more delicate than common onion, making Welsh onion suitable for dishes where subtlety is key.

Storing

Store freshly cut stems wrapped in a damp cloth in the refrigerator for up to 1 week. For longer storage, slice and freeze in a single layer on a tray, then transfer to a sealed bag — use directly from frozen in cooked dishes. Do not wash before refrigerating; moisture accelerates decay.