Lupinus arbustus subsp. calcaratus, commonly known as Longspur Lupine, Spur Lupine, Lime Ridge Lupine, or Quakerbonnet Lupine, is a perennial herb native to the Western United States, including regions such as the Cascade Range and the Sierra Nevada. It is typically found in open woodlands, meadows, and chaparral environments. This lupine species exhibits a rapid growth rate and reaches a height of 1.5-3 feet (0.46-0.9 meters) with a width of 1-2 feet (0.3-0.6 meters). It forms upright stems with palmately compound leaves and produces racemes of blue or purple flowers that are highly showy, blooming profusely in the spring and early summer.

The Longspur Lupine is valued for its vibrant flowers and ability to attract pollinators such as bees and butterflies, making it a popular choice for native plant gardens, pollinator gardens, and restoration projects. It is drought-tolerant once established, requiring low amounts of water, and thrives in full sun to part shade. It is adaptable to a range of soil types, including clay, loam, and sandy soils, provided they have medium to fast drainage. While generally low-maintenance, it can be susceptible to fungal diseases in overly moist conditions. Gardeners should also be aware that lupines can be toxic to livestock and pets if ingested.CC BY-SA 4.0