The Texas Parks and Wildlife magazine reports that more than 225 native Texas plant species are categorized as endangered or threatened. Texas gardeners can help keep rare plants in existence by growing them from seed in home gardens. Individuals interested in growing rare plants should consider the plant's natural habitat, general culture, bloom time and vigor.
Texas Trailing Phlox
Texas trailing phlox (Phlox nivalis), an evergreen shrub in the Polemoniaceae plant family, naturally occurs in the forests and savannas of East Texas. This endangered perennial features dense, needle-like leaves and five-petaled, pink to purple blooms from March through May. Texas trailing phlox prefers sandy to sandy-loam soils. Mature plants reach up to 12 inches in height.
White bladderpod (Lesquerella pallida) naturally grows in the wet soils around the Weches Formation in East Texas. This upright perennial member of the mustard family (Brassicaceae) prefers sandy, wet soils in glades or grassy openings. This plant features wavy leaves and oval, white flowers that bloom in April and May. White bladderpod plants reach between 2 and 25 inches high.
Texas Prairie Dawn-Flower
The Texas prairie dawn-flower (Hymenoxys texana) belongs to the aster family (Asteraceae). This small sunflower features yellow flower clusters on stems that reach up to 6 inches in height. The Texas prairie dawn-flower blooms in the spring, but generally dies by the middle of summer. This delicate plant naturally occurs in the saline soils of Southeast Texas.
Neches River Rose-Mallow
The Neches River rose-mallow (Hibiscus dasycalyx), a member of the Malvaceae plant family, naturally grow in East Texas wetlands. This shrubby perennial reaches heights ranging from 3 to 7 feet tall. Neches River rose-mallow plants feature showy, white to cream flowers with deep burgundy eyes. These five-petaled flowers reach up to 6 inches in diameter. Flowers appear from June through August, and sometimes bloom longer during wet weather. The Neches River rose-mallow prefers wet soils in fully sunny locations.
South Texas Ambrosia
South Texas ambrosia plants (Ambrosia cheiranthifolia), sometimes called Rio Grande ragweed, belong to the Asteraceae plant family and grow in South Texas grasslands. The South Texas ambrosia plant features gray-green to silver foliage and stalks of non-showy, yellow flowers that appear in the summer and fall. This herbaceous perennial plant prefers sandy loam or clay loam soils. Mature South Texas ambrosia plants grow from 6 to 12 inches in height.
The Texas poppy-mallow (Callirhoe scabriuscula) naturally occurs around the upper part of the Colorado River. This mallow plant variety features stiff stems and purple or red flowers. The flowers bloom in May and June, opening every morning and closing just before the sun sets. These flowers do not open after pollination occurs. This rare Texas plant prefers sandy soils. Mature Texas poppy-mallows reach about 30 inches in height.
The Texas snowbells plant (Styrax platanifolius), a small tree or a large shrub in the Styracaceae plant family, grows along the streams running through limestone bluffs in the Texas Hill Country. This perennial plant features green leaves with fuzzy, white undersides. Clusters of bell-shaped, white flowers with yellowish-orange stamens hang off the end of the branches. These attractive flowers bloom in April and May.