Bluebonnets are prized for their blue, spiked flowers that cover hillsides, particularly in Texas. Though certain aspects of bluebonnet flowers seem straightforward, like their color, their classification includes greater diversity than you might expect. Familiarize yourself with different color varieties and interesting facts for more astute categorization of this vivid flower.
The bluebonnet is the state flower of Texas. On March 7, 1901, the National Society of Colonial Dames' choice of Lupinus subcarnosus for state flower won and was passed through the Legislature. Since many thought this species was the least beautiful of bluebonnets in Texas, a fight went on until 1971 when the Legislature made a change; all varieties of bluebonnets from that point forward became classified as the state flower, according to the Texas Cooperative Extension.
The bluebonnet belongs to the bean or legume family (Leguminosae or Fabaceae), according to the Texas Cooperative Extension. Legume classification means these plants are nitrogen producers that add nitrogen to the soil because of the presence of a bacterium called Rhizobium. With a production as high as 100 pounds of nitrogen per acre, bluebonnets have a symbiotic relationship with soil; bluebonnets enrich soils rather than simply taking from them.
As their name suggests, bluebonnets are generally blue. Though the most well-known flower displays blue spiked blossoms on erect stems, an albino bluebonnet appears in white. Additionally, the pink strain is a man-developed color created under the direction of Carroll Abbot. An isolated color gene ensured consistent development of pink bluebonnet shades, according to the Texas Cooperative Extension. "Abbott pink" is named after its creator.
Bluebonnets are annual flowers. Annuals, as opposed to perennials, are plants that experience an entire life cycle within one growing season. The flowers blossom and the plant dies to the ground. As annuals, bluebonnets must be replanted every year.
Bluebonnets are classified as cool-season flowers, according to the Texas AgriLife Research and Extension at Uvalde. Since bluebonnets bloom in the spring, generally in April and May, the best time to plant these hardy flowers is in September and October, according to the Texas Cooperative Extension. The cooler temperatures are necessary for the production of the bluebonnet's large root system.