Santa Fe Botanical Garden

Common name: purple prairie clover

Family: Fabaceae (Bean)

Distribution: Southwestern, Southeastern and Central United States, Southcentral Canada

Habitat: Grasslands, scrublands, woodland openings, riparian zones

Hardiness: USDA Zone 4 (-30 to -20 °F)

Life form: Deciduous shrub/sub-shrub

Occurrence in New Mexico: New Mexico native plant

Growing Conditions: Purple prairie clover occurs throughout much of North America, except for the east and west coasts. It is common throughout the Great Plains and is widespread in New Mexico. It grows in a variety of habitats, including grasslands, sandhills, along riverbanks and in floodplains, in open areas of oak and piñon-juniper woodlands, along roadsides, and in shrubby steppe. It is common in tallgrass, shortgrass, and mixed-grass prairies. Its native range includes areas with 11 inches annual rainfall and up to 53 inches annually (Mississippi). It is most common on sites with exposed soil, where grasses are not growing densely or areas where periodic wildfires occur. It regenerates readily after a fire from seeds banked in soil. Purple prairie clover grows in most soil types. It is often found in sandy to silty loams, however, it also grows in clay, sand and gravelly soils. Good drainage is essential. It grows in full sun or occasionally in part shade. It has a deep taproot and established plants are very drought tolerant. It is easy to grow from seed in spring and does not need stratification, but it is slow to develop into mature plants. Although it is considered an indicator of ecologically mature, pristine prairie, it can also be found in bare and disturbed habitats, such as roadsides.

Description: Purple prairie clover grows ¾–3 feet tall. It is unbranched, but older plants may send up multiple stems from the base, creating a bushy effect. The alternately arranged 2-5 inch long compound leaves consist of 3-7 dark green leaflets, 1 inch long and ⅛ inch wide with scattered translucent dots across the surface. Beginning in early or mid-summer, a dense cylindrical 1-2 inch long spike of tiny purple flowers comprised of 5 small petals and 5 golden anthers blooms as a flowery wreath, which progresses from the bottom to the top of the spike.