Oranges thrive in USDA plant hardiness zones 8 to 11, where high heat increases the sweetness of the fruit. In Texas, oranges are grown primarily in the central to southern part of the state, particularly in the Lower Rio Grande Valley, where land is fertile and inexpensive, though the area is susceptible to hurricanes and requires irrigation. Texas is a key producer of oranges for U.S. consumption and, according to a January 2008 article by Texas A&M professor and horticulturist Julian W. Sauls, represents more than $200 million in value to the state's economy.
The blood orange is unique in that its flesh is a deep red and a truly ripe fruit will taste sweet with overtones of raspberry. This fruit is small and round with a thin skin and seeds. The blood orange is best grown in areas with chilly nights to ripen properly. The most popular blood orange grown in Texas is the Jaffa variety, which is native to Israel and ripens in late winter or early spring. This tree requires full sun and damp soil.
The Everhard is a small navel orange with a thin skin and sweet flavor. Easy to peel and eat, the Everhard was developed in the Texas Rio Grand Valley by a citrus grower named Clay Everhard. The most defining characteristic of this fruit is its hard-to-find or nonexistent navel. The tree, which is considered one of the most reliable, produces its fruit in September. Everhard trees thrive in full sun with regular watering.
The Valencia orange, which is the most planted orange in the world, grows well in Texas. This high-quality, seedless eating orange is firm and round with a medium thick, deep orange skin. Valencias are also good juicing oranges. A Valencia tree will produce fruit in midwinter in warmer areas and in the summer in cooler areas. It is a relatively low-maintenance tree that requires full sun and moist soil.