(Lupinus perennis) Lupine’s dense spires of bright blue flowers signal
the coming of spring. Lupine is the only food
plant for the larvae of the endangered Karner Blue
butterfly. Plants grow 2' tall on sandy loams to very
dry sandy soils. Will not grow well in clay soils.
Perennial. Hardy to zone 4.
Green Thumb Tip Germination is greatly increased by a 7-day cold
treatment in a slightly damp paper towel in a plastic
bag in the refrigerator. Cold-treated seeds can be
directly sown in spring or early summer. Untreated
seeds can be sown outdoors in fall.