Lupines have been cultivated for at least 2,000 years in the Mediterranean area. Lupines have the ability to fix atmospheric nitrogen into the soil, which helps improve the fertility of the soil. There are over 300 types of lupines. They are grown as forage and grain crops that are high in protein. Lupine is a cool-season crop that tolerates spring frosts. They prefer well-drained soil with a coarse texture. Plant lupine seeds in early to mid-April.
Inoculate the lupine seeds with Rhizobium lupini bacteria. This bacteria is available at the same place the lupine seeds are available. Mix together 1/2 ounce of mineral oil per pound of lupine seed with the bacteria in a large bucket. Stir together to ensure that all the seeds are covered with the Rhizobium lupini bacteria.
Remove all the weeds from the planting area. Till the soil up to loosen it with a rototiller. Remove large stones and break up dirt clods.
Level the soil by dragging a rake across the surface. Walk backwards across the area and fill in your footsteps with soil as you go.
Dig a trench that is 3/4 to 1 3/4 inches deep in a long row. Use the handle of the rake to make your rows. Space your rows 6 to 12 inches apart depending on how much space you need between rows. If you plant lupines too deep, the seeds may fail to germinate due to seedling diseases.
Plant your seeds so they are about 3 inches apart. Once they are growing well, they will fill in the space between plants. Fill the rows in with soil by pushing the soil into the trenches with the back of your rake. Sprinkle water over the rows to settle the soil.