Coulter’s lupine, desert or Mojave lupine

Lupinus sparsiflorus

Coulter's lupine is one of the most common spring wildflowers in southern Arizona. This annual has showy blue flowers held on stalks a foot or more in height. In spring it can carpet the desert, often appearing with other spring annuals such as California poppy. The renowned Texas bluebonnets are also lupines.

Grow Coulter's lupine from seed (available as a component of most "spring wildflower" mixes for our area or as pure seed from speciality nurseries) by sowing in fall. Some authorities recommend soaking in water before planting. This annual will reseed to return each year if allowed to stand in place until the seed pods have opened to release seed.

Bajada lupine also grows in our area. In comparison, Coulter's lupine is showier and larger. Bajada lupine has hairier leaves, with pinkish flowers that are almost hidden in the foliage.

Note: both the plant and the seeds of lupine are poisonous.

Wildlife value: nectar plant for insect pollinators. May be a host plant for butterflies.

More Information

Weekly Plant on lupine

Planting Desert Wildflowers from Desert Botanical Garden

Map of distribution in US

 

 

ID Characteristics

 This plant is in the Fabaceae - the legume (pea and bean) family.
 
Coulter's lupine blooming at Academy Village
Coulter's lupine grows to just over a foot tall. The basal foliage spreads about 8 inches. Germination occurs in fall and the plant overwinters as a small rosette of leaves. Both the leaves and stems are hairy.
Coulter's lupine blooming at Academy Village
The leaves can be 5 inches long, most of it leaf stalk. At the end are 7 to 11 narrow, linear leaflets arranged around a center point (this arrangement is called palmately compound), with a total spread of 1-1.5 inches. During the day, these leaflets rotate so they always face the sun. The flower stalk grows from the center of the rosette. the leaves on this stalk are alternatively arranged.
Coulter's lupine blooming at Academy Village
The individual flowers are held on a short stalk (less than 1/4 inch) and are spirally arranged. The newest flowers are at the tip of the stalk.  Each flower is about 3/8 inch long and wide. The center of the upper lip is white with yellow markings. This turns pinkish as the flower ages (said to be a indication that the flower has been fertilized). The rest of the flower is purple-blue and ages to white (see photo below). Occasionally a plant with all-white flowers appears.
Coulter's lupine blooming at Academy Village
The fruit is a pea pod, typical of plants in the pea family. They open to release seed when mature.