The pea-like flowers of lupins grow in dense spires above very distinctive foliage. They will bloom for two months from a spring sowing or early summer from fall sown plants. This cold hardy perennial is native to western North America, and east to Quebec. Continue reading below for tips on how to grow lupins from seed. Lupins are highly attractive to bees and they fix atmospheric nitrogen in the soil.
Season & Zone
Exposure: Full sun to partial shade
Zone: Hardy to Zone 5
Sow indoors 6-8 weeks before last frost. If starting indoors, use peat or coir pots to minimize root disturbance. Lupins work equally well direct sown in early spring when some risk of frost is still possible. They can be direct sown in autumn where winters are mild.
If starting indoors, scarify seeds by chipping, or soak in water for 24 hours prior to sowing. Sow shallowly, a couple of millimetres (1/8″) deep, and maintain a coolish soil temperature of 12-18°C (55-65°F). Seeds should germinate in 14-60 days. Be patient.
Space or thin plants to 30-60cm (12-24") apart to allow for natural spread. After flowering, cut down the stems to the base of the plant. Divide these big plants in early Spring to propagate certain colours. Self-sown plants tend to revert to pale blue.