Welsh onion (Allium fistulosum)

Welsh onion (Allium fistulosum) is a bulbous (or similar) plant that can grow 50cm – 1.5m tall and 10cm – 50cm wide.

This plant has several common names including: Welsh onion, ciboul, onion-leek, Japanese bunching onion, Japanese leek, stone leek or Welsh leek.

This is a semi-evergreen plant that takes 2-5 years to reach full maturity.

Plant profile

Common name: Welsh onion, ciboul, onion-leek, Japanese bunching onion, Japanese leek, stone leek, Welsh leek
Scientific name: Allium fistulosum
Plant type: Bulbs
Habit: Columnar / Upright
Height: 50cm – 1.5m
Spread: 10cm – 50cm
Foliage: Semi-evergreen
Sunlight: Full Sun, Partial shade
Soil: Chalk, Clay, Loam, Sand
Moisture: Moist but well drained
Garden type: Informal Garden, Rock & Gravel Garden
Planting type: Flower borders and bedding
Other characteristics: Plants for pollinators

Seasonal colors

How to plant Welsh onion (Allium fistulosum) – Dalgial, CC BY-SA 3.0, via Wikimedia Commons

Cultivation profiles – Growing Welsh onion (Allium fistulosum) – Krzysztof Golik, CC BY-SA 4.0, via Wikimedia Commons