I have a few beds with similar conditions and these are the plants I've had good luck with:

Day Lillies
Verbina
Purple Sweet Potato Vine
Lantana
Vitex
Esperanza

Im sure there a lot more. If you're interested, check out the Texas Superstar Plant list for further suggestions. http://aggie-horticulture.tamu.edu/cemap/frame.html

Try also the species geraniums. In those conditions mine have spread to become a three foot wide and deep cushion of nice foliage and fuschia colored flowers. Vitex loves it fine as well as roses,tomatoes,peppers (try ornamental pepper plants too) and iceplant.

some sun/heat tolerant plants i've grown are roses, amarylis, daffodils, gladious, cannas, daylilies, aloes, sunflowers.

if you want fruit trees, grapefruits, kumquats, mandarin oranges, lemons, limes, pomegranites, persimmons, pears, figs. they survive our summers, and our mild winters.

Try this database provided by the Houston Chronicle:
http://www.chron.com/homeandgarden/hgsearchtool/?cat=plants