Fickle Desert Blooms: Opulent One Year, No-shows the Next

When it rains, the desert blooms, but what is the complex process at work? The wild, improbable nature of the desert spring in the American Southwest and northern Mexico is captured by author Diana Kappel-Smith and photographer Tom Wiewandt. Most of the time desert flowers are invisible, spending their lives as seeds waiting for just the right amount of moisture to germinate. Each variety has its own strategy. "Where rosette plants put in months of careful preparation before sending up a flower stalk, bellyflowers make a practice of germinate-and-go-for-broke."

The interdependence between the plants and the birds and insects that feed on their necter and thus pollinate them is a delicate balance, too. In general, the more barren the desert is, the more rare and astonishing the flower show will be. A good flowering year may come only once in a decade or two.