How to grow Lupin

Lupinus polyphyllus · lupine

A hardy perennial with tall spikes of pea-like flowers from late spring to midsummer, usually living only two to five years. All parts are poisonous, and the seeds can cause severe discomfort if eaten.

Quick facts

Type	Flower
Family	Fabaceae
Light	Full sun
Soil pH	5.5–7
Frost	tolerates light frost
Soil for sowing	from 5 °C
Germination	14 days
Where it grows	Greenhouse, Open ground

When to plant

Planted as a young plant from a nursery while it is dormant — in early spring before the buds open, or in autumn after leaf fall.

Frost dates · When to plant

Care

Greenhouse

Stage	Watering	Temperature	Feeding
Germination	every 7 days	—	—
Growth	every 7 days	—	—
Flowering	every 7 days	—	—

Open ground

Stage	Watering	Temperature	Feeding
Germination	every 7 days	—	—
Growth	every 7 days	—	—
Flowering	every 7 days	—	—

Growing notes

Light

Needs full sun; in shade it flowers poorly. In hot summers light afternoon shade helps.

Soil

Well-drained, moderately fertile soil, neutral to slightly acid. It grows best where summers are cool and dislikes heat with high humidity.

Care

Plant potted lupins in spring or early summer and water them regularly through the first summer; after that they are fairly drought tolerant. No feeding is needed unless flowering is poor. Cut spent spikes to the base to get more flowers and prevent self-seeding, and stake tall plants. Watch for slugs on young plants, lupin aphid and powdery mildew. From seed, nick the seeds and soak them for 24 hours, then sow in early to mid spring; they germinate in 10–14 days at 10–15 °C and usually flower the following year.

Pests and diseases of Lupin

Sources

Figures checked against these sources.