If you are looking for a drought tolerant ground cover, consider low growing, spreading junipers as they fit the bill. For best results avoid super short varieties, less than 10” high at maturity, such as “Wilton Carpet,” or “Bar Harbor,” as weeds more easily penetrate their thinner leaf canopy. Instead, grow varieties that are between 1 to 2 feet in height like “Broadmoor,” “Buffalo,” or “Calgary Carpet.” These varieties have less weed problems and are very hardy. They will need more water during their first year or two to get established.