I would contact your local cooperative extension office. They can help you optimize your soil, and help you choose the right plants for your site. Also keep in mind that even fairly drought-tolerant plants typically need some additional watering the first year or two after planting.
I agree with Steve. Amending the soil to improve its current condition is the key. This way the water can sink in as well as drain better. Roses do need ample water two to three times per week and are heavy feeders, hence a bloom booster every 10-14 days. Check out the Antique Rose Emporium in Texas for the best advice about roses and other flowers in your area. Also the Master Gardeners at the Extension office.
Patsy, the Texas "SmartScape" web site has information on more than 200 plants, shrubs and trees that thrive in West Texas. It was developed as a combined effort of a number of city governments and water districts.
Here is a list of "Ornamental Plants for Far West Texas" from the extension service at Texas A&M:
The above is the best advice you can get!