Caesalpinia gilliesii - Desert Bird of Paradise
This showy desert bloomer is even more spectacular in person than in pictures. The large yellow flowers seem tropical, with long red stamens, amazing against feathery green foliage.
Originally from Argentina, this desert beauty has naturalized in the Southwest, is tough and undemanding despite its fragile appearance. Happy in scorching sun or part shade, it looks best with an occasional deep watering, but will tolerate the worst drought, and it's hardy down to 5 degrees. A carefree plant in zones 8-10, it does fine indoors in a bright window elsewhere.
Hummingbirds love it. Deer leave it alone.