The lupine plant displays a tall spike of colorful blossoms that are eye-catching. The wild plants grow up to 5 feet tall in well-drained soil that is coarsely textured. North America is the native ground for more than 200 wild species of lupine including the famous Texas bluebonnet. The lupine has been hybridized as a hardy perennial garden plant. Hybridized plants have been developed to reach a shorter height than the original wildflowers.
The lupine was cultivated in the Mediterranean region of the world more than 2,000 years ago. It has also been grown in regions of Australia, Germany and Poland as a non-alkaloid crop for human and animal consumption. This type of lupine is know as "sweet." The sweet white lupine hybrid seed has been chosen over the years for the safer protein-rich nutrients for animal feed.
Lupine seeds are planted in early spring 3/4 to 1 3/4 inches deep in the prepared garden soil. The bean-like seeds are sown 7 to 10 inches apart in rows when planted for grain production. The plants emerge and vegetative growth is slow as palm-shaped leaves emerge. Lupine plants will grow in new areas after the seeds are transported by birds and animals that feed on the plants.
A sturdy stalk-like growth with a tight bud mass grows up from the small green plant. The bud can measure 5 inches long or more during the early stages of growth. The color soon begins to show as the spear tip-shaped bud matures and develops into individual blossoms.
The bud increases in size as the stalk grows taller. Small, colorful blossoms open giving a ruffled effect to the bottom of the bud. More stalks emerge that will produce buds and flowers as the plant grows.
The bottom blossoms weaken and wilt as the tip becomes fully blossomed. The seed pod forms and increases in size as the seeds grow. The outer layer of the seed pods have a furry appearance. The pods should be checked if they are to be hand-harvested for new plants in the future. If the pods turn black they may split open at any time and the seeds will self-scatter in the area.
Varieties of lupine are toxic to animals and humans. Professional growers are aware of the proper plants to grow for food. Animals should not be allowed to graze on any lupine plant when there is no proof that it is alkaloid-free.