How to Care for Lupine Flowers

Lupine flowers prefer partial shade to full sun.

Members of the family Fabaceae, lupines can come in annual and perennial varieties and grow tall spikes of sweet-pea-shaped flowers. These deer-resistant blooms prefer partial shade to full sun. Lupine flowers propagate from seed and prefer to grow in USDA hardiness zones 5 through 8, depending on the variety, in well-drained soil with a pH between 4.5 and 7.5. Far from fussy, lupine flowers display their red, white, yellow, blue or violet blooms in the spring and summer with minimal care once established.

Things You'll Need

• Soaker hose
• Fertilizer
• Insecticidal soap
• Mulch

Instructions

1. Maintain moist soil after planting and throughout the growing season. Use a soaker hose, which will deliver deep watering down to the roots of the lupine flowers. Lupines require at least 1 inch of water per week through both supplemental watering and rain.

2. Feed the lupine flowers a diet of fertilizer that is rich in phosphorous and low in nitrogen. Follow the label instructions for application recommendations. Most lupines thrive when given a dose of fertilizer once a month during the growing cycle.

3. Deadhead the flowers regularly. Snip them just below the flower; they will re-bloom. If you are growing perennials, cut the flower stalks down to the base after flowering is over.

4. Remove pests from the lupine flowers using an insecticidal soap. Although lupines have few pest problems, they are prone to aphid infestations now and then. Apply the insecticidal soap according to manufacturer's instructions.

5. Spread mulch around the lupine flowers to control weeds. Weeds will compete with the lupines for water, so a three- to four-inch layer of straw or bark chips can help control the problem. Mulching will also protect the roots of the lupine flowers and improve drainage.

Tips & Warnings

• Collect the seeds of your lupine flowers in the fall to grow more the following spring. Pick the seedpods when they turn yellow. Peel the pods open and pour the seeds into a plastic bag. Place a damp paper towel in the bag, seal and store in the refrigerator until spring.

• Do not over-water your lupines. Standing pools of water above and below the soil can cause root rot. If the soil already feels moist to a one-inch depth, do not add more water.

References

• Planet Natural: Growing Lupine
• Backyard Gardener: Lupinus lupine

Resources

• Wise Acre Gardens: Lupine
• The New Perennial Club: Lupinus Woodfield Hybrids
• Grow It: USDA Hardiness Zone Maps