While these iconic Arizona cactuses are special for many reasons — their beautiful flowers, their lifespan ... according to ...

The hardpan layer prominent at Tucson is not well developed. The winter annuals and the larger shrubs and cacti are absent. Most of the plants are perennial herbs. The root systems generally penetrate ...

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 ...