A spring-time favorite, growing lupine (Lupinus polyphyllus) provides flower gardeners with a brilliant array of colors. Plants have stiff, erect flower spikes of 1-4 feet that emerge from horizontal foliage. Flowers are similar to those of peas or sweet peas, and grow in large, crowded racemes of deep blue, purple, yellow, pink or white. Found growing wild throughout most of the northern United States. Short-lived perennial.
Easy to grow, lupine thrives in cool, moist locations. It prefers full sun to light shade and average soils, but will tolerate sandy, dry soil. Plants develop long taproots, so loosen the soil to a depth of 12-20 inches, using a roto-tiller or garden fork. They will not grow in clay.
Tip: For dramatic results, mass lupines in the border or scatter them throughout the cottage garden.
How to Plant:
Lupine can be grown from seeds, cuttings or divisions. If growing from seed, germination is greatly increased by a 7-day cold treatment. Place seeds and slightly damp paper towels in a Ziploc bag and store in the refrigerator. Another method would be to chip seed or soak in warm water for a 24 hour period. Treated seeds can be directly sown into a seedbed in spring or summer until August 1. Untreated seeds can be sown outdoors September-November. Plants grown from seed will bloom their first year. Pinch-off spent flowers to prolong the blooming period. Apply an all-purpose organic fertilizer once a month to promote healthy plants and large blooms.
Note: Do not transplant, as the long tap root is delicate and if damaged, the plant will fail.
Insects and Disease:
Lupine does not have many pest problems associated with it. Occasionally, it will become infested with aphids. Watch closely and apply insecticidal soap or other natural pest control, when necessary.
Seed Saving Instructions:
Ripe seed pods naturally explode. When the seed pods begin to turn yellow and the seeds “rattle” inside, they are ripe. Place in a screen box where they can explode freely and simply pick up the seed.