Plants that do well in southwest desert gardens are not only drought tolerant but also heat tolerant. Heat tolerant plants often develop extensive root systems that allow them to obtain moisture from a wide and deep area. They may have silvery leaves to reflect excess light. Heat stress can be further reduced by providing afternoon part shade to lower water needs. Thick mulch surrounding non-desert plants will reduce moisture evaporation from the soil and keep roots cooler.
For desert climates, in the mountains, select plants that accept pH 7.0 (neutral) soil. In valleys, select plants that accept pH 7.5 - 8.5 (alkaline) soil. Acid-loving plants will require heavy soil modification and periodic soil maintenance to survive. Water supplies in the desert are also slightly alkaline, putting further stress on acid-loving plants.
Choose desert-compatible plants that desperately hungry wild critters dislike. These drought resistant plants are less tasty to wildlife and often grow back quickly when nibbled.
For fruit plants, choose varieties that need 300 winter chill hours or less. Chill hours are those hours in winter below 45°F and above freezing. Some food crop trees, such as Pistachio, will not produce a crop in hot desert climates because of insufficient winter chill hours.