Oklahoma experiences a semi-arid zone in the western part of the state and a humid subtropical climate in the eastern regions. The state of Oklahoma falls within the United States Department of Agriculture (USDA) Hardiness Zones 6 and 7. Oklahoma gardeners should select flowers according to appropriate zone, general culture, flower color, bloom time and intended use.
Indian mallow (Abutilon fruticosum), a perennial in the Malvaceae plant family, reaches between 2 and 3 feet in height. This mallow variety features hairy, green leaves and single, yellow to orange flowers that bloom from June through October. The Indian mallow naturally occurs in dry soils around Oklahoma woods, cliffs and slopes. Deer and goats often feed on this plant. Oklahoma gardeners primarily use the drought-resistant Indian mallow in xeriscapes and butterfly gardens.
Sundrops (Calylophus berlandieri), also called Berlandier's sundrops, belong to the evening-primrose family (Onagraceae) and grow along Oklahoma roadsides and woodland margins. This perennial plant features spiny, green leaves and large yellow blossoms that bloom from March through September. Mature plants reach between 12 and 36 inches in height. This plant likes moist, rocky or sandy soils in partially to fully sunny locations. Sundrop plants work well in rock gardens.
The black Sampson (Echinacea angustifolia) belongs to the aster family (Asteraceae) and prefers dry soils in partly shady to fully sunny locations. Black Sampson plants feature hairy, green leaves and stems ranging from 18 to 24 inches in height. Flowers bloom from May through June, featuring drooping, pink to purple petals surrounding dark, spiny centers. Oklahoma gardeners often use black Sampson plants in prairie gardens and wildflower meadows.
Purple groundcherry plants (Quincula lobata), also called Chinese lanterns, only reach up to 6 inches in both height and spread. This low-growing perennial bears fuzzy, grayish-green leaves and blue to purple flowers that bloom from March through October. This potato family member (Solanaceae) prefers dry soils in lightly shady to fully sunny locations. Oklahoma gardeners often plant the purple groundcherry as groundcovers.
Rose Pogonia Orchid
The rose pogonia orchid (Pogonia ophioglossoides), also known as the beard flower, belongs to the Orchidaceae plant family. This orchid variety blooms fragrant pink flowers with yellow or white beards. These flowers display from May through August. Mature plants range from 12 to 36 inches in height. The rose pogonia orchid works well in moist meadows and bog margins that receive full sun.
The zigzag iris (Iris brevicaulis) naturally occurs in wet marshlands across Oklahoma. This Iridaceae family member prefers somewhat acidic soils that receive at least partial sun. The zigzag iris bears long, green leaves and zig-zagged stems. The flowers display in March and April, featuring purple, white or blue flowers with dark sepals and petal veins. Oklahoma gardeners often plant zigzag irises around bog gardens, water gardens and ponds.