Organ Pipe Cactus National Monument - Plants

The organ pipe is a large cactus found rarely in the United States, although it is common in Mexico. The monument encompasses the bulk of its U.S. population. Like its fellow cacti and other desert inhabitants, the organ pipe is tuned to the rhythms of the sun and the infrequent rains. A glutton for heat and light, it grows on south-facing slopes where it can absorb the most sun. This location is critical during winter months, when severe frosts can kill the cactus. But when it blooms in the heat of May, June, and July, the organ pipe waits until the sun goes down to open its tender lavender-white flowers. Other types of cactus bloom at night, too, but many also bloom during the day, exposing there flowers to the sun. Day or night, the summer display of many different cactus blooms is one of the desert's flashiest spectacles, as the brilliant flowers of yellow, red, white, and pink bring color to the landscape. It is a show upstaged only by the springtime explosions of gold poppies, blue lupines, pink owl clover, and other annuals after a wet winter.