The annual pictured to your right, moss rose (Portulaca grandiflora), is a drought-tolerant plant. If you have a dry spot in your yard, an area blasted by the sun all day long and not exactly blessed with the finest soil, then you may have trouble getting anything but weeds to grow there. If you prefer perennials, you'll find many examples listed in my drought-tolerant plant resource. But moss rose is an excellent solution if you crave the long-blooming quality of annual flowers.