California has an unofficial state flower: in addition to the golden California poppy, the hillsides are covered with purple-blue lupines in many areas. The Texas bluebonnet is in the Lupinus genus. Belonging to the pea plant family, the lupine includes 165 species and occurs in most of the United States, including Hawaii and Alaska, making them adaptable and suitable for use in almost any landscape.
Wildflowers Like Wild Areas
Lupines are not very particular about the soil where they grow. A common roadside plant, the lupine is often spotted on sunny hillsides and meadows in spring. By midsummer, the plants have set their seeds and are looking pretty dead---they are considered a short-lived perennial and prefer the cooler, wetter conditions in spring.
How to Grow Lupines
If your garden has an area with dry, sandy soil and partial shade, you'll be able to introduce lupines. Because of their long taproots, be sure to loosen your soil down to at least 12 inches before you plant the area. Clay soil is not suitable for lupines. Plant seeds, make stem cuttings or root divisions of existing plants.
Put seeds between damp paper towels inside a plastic zipper bag in your refrigerator for at least one week before you plant them or soak seeds in warm water for 24 hours before planting them. Continue planting seeds you have treated until early August for blooming the following spring. Sow untreated seeds from September through November.
Insect Pests That Can Affect Lupines
Lupines are quite hardy and only aphids seem to bother them. If they become a problem, spray your plant with insecticidal soap.
Conditions Lupines Do Not Favor
You won't find many types of lupines growing close to the ocean because they don't grow in salty soil---two exceptions are the yellow bush lupine and the purple flowered beach lupine, which grow behind the protection of sand dunes. They also do not care for soil that is high in lime. Only a few lupine species grow in areas where it becomes very hot and dry early in the year, such as desert regions of the Southwest.
They do not respond well to transplanting because their taproot is fragile and can easily become damaged when you dig up a plant and attempt to move it to another location.
Uses in Home Landscapes
When you plant lupines in poor or sandy soil in your garden, they make a nice mid-height addition to flower gardens and borders. Because they finish blooming by midsummer, they add color to scrub areas early in the season. You can plant other later-blooming flowers in between your lupines for continuous summer color. Lupines blend well with penstemons, snapdragons, tall varieties of marigolds and wildflowers such as California poppies.