Full to part sun, but flowering is reduced in part shade
Bloom Period and Seasonal Color
Lupines bloom in early to mid summer
Lupines are striking annual and perennial flowers that are widely adapted. Wildflower versions can be found in the South (called blue bonnets) or along roadsides in the mountain of the North and West. These legumes are often found growing in the wild in clumps and when in bloom can turn the ground into a carpet of color.
Lupines are hardy in USDA zones 3 to 7. Lupines come in a variety of flower spike colors depending on the species and variety. There are lupines with white, pink, yellow, blue, purple and red colored flowers. Hybrid series feature a selection of colors.
While lupines look great naturalized in a meadow, orchard or field, they also are good flower and cut garden plants. The perennial versions have a taproot, so are long lasting, drought tolerant and hardy. Annuals and perennials will self-sow, and spread over time.
When, Where and How to Plant
Plant lupine seeds or plants in spring or summer on a sunny site with loose soil. Lupines don’t grow well in clay soils. Loosen the soil before planting. They also like a slightly acidic soil so add sulfur, based on a soil test, to lower the pH before planting.
Lupines can be annual or perennial depending on the selection. Annuals will bloom the first year after seeding. If growing from seed, soak the lupine seed in warm water over night before sowing to enhance the germination. Plant in loosen, compost amended, soil spacing the seeds 12 inches apart. Once germinated, thin the seedlings to 2 to 3 feet apart. Nursery grown plants tend to be perennials. Plant these plants in spring or summer at the 2 to 3 foot spacing. Group plants together for a better visual effect.
Lupines love cool soil and temperatures. If grown in the South, look for locations in the garden with afternoon shade to help the plants survive the summer heat and mulch.
Lupines can be low growing wildflowers or tall stately perennials. If growing the taller selections in a windy location, support these with stakes and twine, or Velcro plant ties, to support them from falling over. The winds can not only break a flower stalk, but also cause it to bend.
Lightly mulch lupines in hot climates to keep the soil cool and moist. Perennial lupines are drought tolerant so once established rarely need extra watering. Fertilize in spring with a layer of compost. Since these legumes have a taproot that fixes nitrogen, they need little additional fertilizer and help plants around them grow by breaking up heavy soils.
Deadhead spent flowers immediately after blooming and side shoots may form that will flower again later in summer. Cut back the whole plant to the ground in fall after the foliage starts to yellow.
To encourage self-sowing, leave some of the flowers to set seed. Lupines don’t divide well, and spread mostly by seed.
Lupine flowers can have damage from aphid insects. Their feeding can deform flower stalks and cause it to bend. Spray the lupines with insecticidal soap to kill aphids. Also, you can just wash aphids off the plants with a strong spray of water from a hose. They won’t climb back up on the plant.
Lupines can also get powdery mildew disease and the plant can become unsightly. Cutting it back in summer isn’t advised since the plant needs to have leaves to rejuvenate the roots for next year’s flowering. Control powdery mildew by spacing plants further apart to encourage air circulation, cleaning up plants well in fall and spraying Bacillus subtilis or Serenade on plants at the first sign of the fungal disease.
Companion Planting and Design
Lupines are great plants grown en mass on a bank, field, meadow or orchard. The species types naturalize well. You can also grow them in the garden with other flowers such as tulips, daffodils, California poppy, Oriental poppy, peonies, baptisia, yarrow, mountain bluette, and perennial geraniums.
The ‘Russell Hybrid Series’ is probably the most widely known selection of lupines for the garden. The series features varieties in a range of colors such as yellow, red, blue, white, bi-color and purple. Plants grow 2 to 3 feet tall and are long lived. ‘Tutti Frutti Series’ features also a range of varieties and flower colors. This hybrid is a good cut flower and is a reliable perennial.
Texas blue bonnets are popular, perennial wildflowers in the South. The Arroyo and Golden lupines are self-sowing annual wildflowers in the West. ‘Pixie Delight’ is a dwarf annual type that only grows 12 to 18 inches tall.