Saguaro Cactus

Saguaro Cactus
Cereus giganteus
Arizona state flower


Description: The saguaro cactus is one of the dominant forms in the Sonoran Desert. While a young saguaro takes nearly a decade to reach one inch tall, over many decades it can reach heights of fifty feet, making it the largest cactus in the United States. The saguaro is a single-stemmed, columnar cactus supported by woody ribs. The skin of the cactus is light green and waxy. Spines are clustered down the length of the ridges. At seventy-five years old, the cactus begins to sprout arms that grow parallel to the body. As many as fifty arms can be found on older saguaros with ages estimated to be 200 years old. A cactus that large can weigh over eight tons.1
The saguaro flowers from May to June. The flowers have waxy petals that are a smooth, creamy white color. The flowers open at night, awaiting pollination by bats, birds, and insects. When the fruit ripens, it reveals a juicy red pulp that is enjoyed by many desert dwellers, including people. The Tohono O'odam Indians use the fruit to ferment a beverage similar to wine.

Habitat: The saguaro grows on desert slopes and flats, doing best on bajadas--gently sloping plains at the foot of the desert mountains.1 The saguaro begins life under a "nurse" plant, usually a palo-verde or mesquite tree. The tree benefits the saguaro by providing shade and increased water availability during summer, as well as protecting it from winter frosts.1

Range: The saguaro grows in the Sonoran desert, which covers extreme southeastern California, southern Arizona, and adjacent northwestern Mexico.

Status: The cactus is protected by the Arizona Native Plant Law. No part of the cactus may be taken without a permit.

The Saguaro in Pima County: As far back as the early 1900's, the saguaro enchanted visitors to this state. The saguaro was often loaded on trains and shipped to different cities to be displayed in expositions and in parks. In March of 1915, San Francisco received a thirty-five foot tall saguaro for an exposition. 2 In May of that same year, Tucson Day was declared in the city of Stockton, California when they received a saguaro for the Stockton Acres Park.3 Currently, Pima County is home to two of the largest saguaros recorded in the state.4 The saguaro is an integral part of the desert, providing food and shelter for many desert species.


1 September 1, 1999. Website:

2 Arizona Daily Star. March 1, 1915. "Giant Sahuaro Sent Frisco Exposition is 35 Feet Long and has Eight Large Prongs; Took 20 Men 4 Days to Pack." From the Ted Knipe Collection, Arizona Historical Library.

3 Arizona Daily Star. May 25, 1915. "Sahuaro Cactus is Shipped to Stockton." From the Ted Knipe Collection, Arizona Historical Library.

4 9/2/99 Website:

back to Keystone Species