Allium Cernuum

This month’s plant is a member of the Allium family noted for its beautiful clusters of pink flowers in mid to late summer that attracts pollinators from far and wide. As a member of the onion family, the tender young stems can be used where you would use chives and the bulbs can be used raw or cooked – though they have a very strong flavour.  The Plant Description and In the Garden sections, below, provided by Shaun Booth of In Our Nature

Common Name: Nodding Wild Onion 

Scientific Name: Allium cernuum 

Family: Liliaceae (lily family) 

Alternate Common Names: Lady’s Leek, Nodding Pink Onion 

Plant description: Nodding Onion features a tuft of basal leaves originating from a bulb. It’s arching, grass-like leaves reach up to 30cm long and 1cm wide. The leafless flower stalks rise slightly above the foliage and bend downwards at the top, producing a nodding umbel of flowers (hence the name “Nodding” Onion). All parts have a strong onion smell. 

In the Garden: Nodding onion is a small but showy plant that thrives in tough sites. For best effect, plant it in large groupings. It doesn’t like competition from taller plants so plant accordingly. This is a very well-behaved, clumping plant but may self-seed in optimal conditions. 

Lifespan: perennial 

Exposure: part shade to full sun 

Soil Type: humus-rich, neutral to alkaline soils but will adapt to acidity, sand to clay 

Moisture: medium dry to moist 

Height: 40 cm 

Spread: 8-15 cm 

Bloom Period: Jun, Jul, Aug 

Colour: pink (white) to light lavender 

Fragrant: (Y/N): Y (leaves produce an onion-like scent when crushed) 

Showy Fruit (Y/N):

Cut Flower (Y/N):

Pests: no serious insect or disease problems 

Natural Habitat: prairies, rocky outcrops and at the edge of dry open woodlands 

Wildlife Value: supports a variety of generalist pollinators including native bees and the nectar attracts hummingbirds and butterflies 

Butterfly Larva Host Plant For: Hairstreak butterflies (Satyrium spp.) 

Banded Hairstreak caterpillars feed on Allium Cernuum leavs and flowers.

USDA Hardiness Zone: 3-8 

Propagation: Spreads by seed and bulb offshoots. Sow seeds in the fall or provide 60 days moist, cold stratification if spring planting. Cover lightly with soil/growing medium. Plants benefit from being divided every third year or when 8-10 bulbs appear in the clump. Plants may be divided any time of the year. 

Additional Info: Walnut (juglone) tolerant. Nodding Wild Onion is rare in Ontario – it is believed that the only natural populations left are those growing in alvar habitat on Pelee Island. In New York it is classified as Threatened.