There are 200 species of lupins, according to Reader's Digest Encyclopaedia of Garden Plants and Flowers. The most popular varieties are the perennial Russell strains, which are hardy from garden zone 4.
Growing Lupins from Seed
Sow lupin seeds directly in the ground in early spring or early autumn. Use ordinary garden soil amended with compost. Plant the seeds 18 inches apart to avoid overcrowding.
Grow Lupins from Basal Cuttings
A basal cutting is the removal of smaller stems taken at ground level. Basal cuttings ensure the new plant has the same colour and form as the mother plant. Dip the base of the cuttings in rooting hormone and plant them in pots filled with loose soil. Place pots in protected areas away from the midday sun. Leave the cuttings to root for three to four weeks. Test them by pulling up one or two. If they give easily, they haven't rooted. Plant them out by late summer or early fall.
Naturalising With Lupins
Lupins are prized by cottage gardeners for their height, hardiness, form and outstanding colours. With good garden culture, they will grow to 3 feet tall. Lupins lend themselves well to naturalising along garden boundaries under tree canopies where few other tall flowering plants will grow.