The saguaro, Carnegiea gigantea, is the largest cactus in the United States and native to Arizona. In 1931 the opulent white blossom of the Saguaro Cactus was designated as Arizona’s state flower. The best time of year to see these cactus bloom is April through June.
The Saguaro cacti mainly grow in the Sonoran Desert of Arizona. When a Saguaro cactus reaches 35 years of age it begins to produce blossoms. Amassed near the ends of the branches, the green buds bloom into milky-white flowers. The Saguaro flower blooms after sunset and last only one day.
At the top of the flower tube is a compact group of yellow stamens. The saguaro cactus has more stamen on its flower than any other cactus. If conditions have been favorable for the Saguaro you could see hundreds of blossoms on a cactus.
Pollinators like birds, insects, and bats are attracted to the nectar that collects at the bottom of the flower’s 4 inch tube. A Saguaro blossom can only be fertilized by cross-pollination.
Only a few Saguaro flowers bloom each night and close by late morning; thus, giving a greater opportunity for pollination.
This elegant desert pageant occurs for about 2 months. From living in this area, we have to say it is hard to decide the exact dates but end of April to mid June would be notable.
bird pollinating the Saguaro cactus blossom
Pollinated flowers form a vivid red fruit filled with thousands of black seeds. The fruit is eaten and digested through which its dispersed throughout the desert.
While traveling Arizona we stopped at Saguaro National Park, in Tucson. The park is located in the Sonoran Desert.
The giant cacti, called Saguaros, are protected and preserved within the park.
After a single rainfall, Saguaros can soak up to 200 gallons of water through their huge network of roots that lay just 4-6 inches below the desert surface. That is enough water to last this giant cactus an entire year!
A saguaro expands like an accordion when it absorbs water which can increase its weight by up to a ton.
In 1931, The Saguaro’s Blossom became the Arizona State Flower.
The Saguaro Cactus blooms April through June. Its flowers are creamy white and numerous. Up to a hundred flowers can bloom on one Saguaro Cactus!
The saguaro blossom opens after sunset and by the next afternoon the flower is wilted. The white cactus flower repeats itself night after night. During the few hours the saguaro flower is open birds, bats, and honeybees pollinate them.
Later in the summer, the cactus flowers that were pollinated will become red-fleshed saguaro fruits that are enjoyed by the local bird population. The saguaro cactus is also known as the pitahaya, sahuara and giant cactus.
The Saguaro often begins life with a nurse tree or shrub which can provide shade and moisture for the germination of life. This Saguaro grows slowly — only about an inch a year — eventually becoming very tall; reaching heights of 50 feet. The largest saguaro cacti, with more than 5 arms, are approximately 200 years old.