Showy annual wild flower that is easily grown from seed in average, dry to medium moisture, well-drained soils in full sun. Tolerates light shade. Favors somewhat poor soils because of reduced competition from other plants. Spreads invasively by self-seeding, particularly in dry open areas. Plant seeds late March to May.
Chamaecrista fasciculate, commonly known by a large number of common names including partridge pea, prairie senna, golden cassia, large-flowered sensitive pea, sleeping plant, and locust weed, is a showy annual flower in the legume family that typically grows to 1-3’ tall. Shorter plants stand erect, but taller plants tend to sprawl. It is native to a variety of habitats including rocky open woods, upland slopes, ridges, bluffs, prairies, grasslands, rocky fields and open thickets in the eastern, mid-western and Great Plains sections of the U. S. from Massachusetts to South Dakota south to New Mexico and Florida.
Large, showy, yellow flowers (to 1” across) bloom from the upper leaf axils in short clusters (each to 2-6 flowers) from late June to September. Each flower has 5 rounded yellow petals and 10 stamens (6 red and 4 yellow). Flowers are borne on stems clad with alternate, pinnate-compound leaves, each leaf having 8-18 pairs of small, narrow, linear-oblong 2/3-inch long leaflets. Leaves will usually fold together (collapse) when touched giving rise to the common name of sensitive pea. Leaves are also sensitive to daylight, folding their leaflets in late afternoon each day as darkness approaches. Flowers give way to narrow, flattened, dehiscent seed pods (each to 2 1/2” long). Each pod is initially green but matures to brown before splitting open on both sides in fall to explosively expel the seeds within. Seeds are regularly consumed by birds. Plants provide cover for game birds and browse for deer. Flowers are a good nectar source for bees and butterflies.