Although the Southwest is not a region known for its fall color, with careful selection, you can incorporate blasts of red, yellow, and golden color into your garden. In years when hard freezes are not early, the color lasts into December and even January. Try the following tree and shrubs.
Chinese pistache (Pistacia chinensis, Zones 7-9): Appreciated as one of the few desert-adapted shade trees to provide radiant fall color, the venerable Chinese pistache has a new twist: a grafted variety named Sarah's Radiance. This female clone has a uniform shape, increased cold tolerance (hardy to Zone 5), and more intensely red fall foliage, tinged with pale purple. Because it is a grafted specimen, it is only available in large-container sizes. Ask for it at local nurseries that have a good selection of woody plants and trees.
Flame-color sumacs: A new prostrate variety of squawbush (Rhus trilobata 'Autumn Amber', Zones 4-6) grows only 2-3 feet tall and has the same flaming yellow to red lobed leaves as its larger relative. For gardeners in slightly warmer areas, desert sumac (Rhus microphylla, Zones 6-9) forms a dense 6-foot-tall mound that makes an excellent deciduous hedge.
Mexican buckeye (Ungnadia speciosa, Zones 8-10): The compound leaves of this large shrub turn a brilliant yellow in fall and make a good backdrop for smaller plants. In spring, pink flowers emerge before the leaves. Mexican buckeye reaches a height of 15 feet with a similar spread. It is hardy to Zone 6. Mexican buckeye is available at nurseries specializing in native plants.