Plants growing in a part sun/part shade receive four to six hours of sunlight each day during the growing season. In Texas, morning sun exposure is best because it prevents mildew by drying dew off the plants and is not as harsh as afternoon sun. There are several native blooming perennials that are reliable performers for partial shade locations in Texas.
Coral bean (Erythrina herbacea) grows to 4 feet tall and wide in partial shade locations throughout the state. It grows best when provided supplemental water in the driest areas, but it is native to the state of Texas. The red flowers are produced on numerous spikes in mid to late summer followed by attractive seed pods containing poisonous beans. The branches are covered with sharp thorns and remain evergreen south of U.S. Department of Agriculture Plant Hardiness Zone 8, which is the middle section of the state.
Turk's cap or wax mallow (Malvaviscus arboreus var. drummondii) is a perennial plant that grows throughout the state in part/shade and full sun. It has bright green maple-shaped leaves and produces unusual rounded bright red flowers that attract butterflies and hummingbirds all summer. It grows to 4 feet tall and 2 feet wide and multiplies readily throughout the garden from the roots.
Texas Rock Rose
The Texas rock rose or Texas swampmallow (Pavonia lasiopetala) is a blooming perennial deciduous plant in Zones 8 and 9, but often is seen in cooler parts of the state in containers and protected areas. It is extremely drought tolerant and is used in commercial landscapes and highway medians. It produces pink flowers resembling hibiscus flowers on wiry stems during the summer and grows to 24 inches high.
Esperanza (Tecoma stans) is a deciduous shrub that thrives in hot, dry locations in full sun to partial shade. It grows to 6 feet tall and 4 feet wide in Zone 8 and warmer where is is a perennial that often dies to the ground in winter. Zone 8 is the begins in the middle part of Texas. It is used as a container plant or annual in other locations. The outstanding feature is the multitude of bright yellow tubular flowers produced in the summer followed by long seed pods.
Flame Acanthus or Wright's desert honeysuckle (Anisacanthus quadrifidus var. wrightii) is a deciduous shrub that grows in Zones 7 and warmer which is the southern three-fourths of the state. It is a drought-tolerant blooming shrub that produces red-orange tubular flowers during the hottest part of the summer when little else is blooming. Cutting back the flame acanthus to the ground in late winter helps the plant maintain a bushy appearance.