Welcome, Gloellen!
They like rich soil, full sun--unless you live in the lower Rio Grande Valley--and ample water. I would also feed them a balanced plant food regularly, since they are pretty hungry plants. Each stem will produce 2-3 spikes of flowers, then start to turn brown and die back. They will look better if you remove old stems regularly, and new ones come up to replace them. If you live in north Texas, or higher elevations in west Texas (USDA zone 8a, or colder) dig the rhizomes up when the first frost turns the stems brown, and save the rhizomes inside a frost free storeroom or garage, in slightly moist sawdust or "forest mulch". Plant them out again after the average date of last frost the next spring. In warmer areas, just cut off the brown stems and leave them in the ground. Along the Gulf Coast, you may have to divide them every spring in self defense--they multiply like rabbits. They can grow well in shade, but you may only get leaves, which are sometimes pretty enough by themselves!