Dimensions Guide

What Is the Largest Cactus in the World?

The largest cactus in the world is the Saguaro cactus, scientific name Carnegiea gigantea, a species of the genus Carnegiea. It is indigenous to the Mexican plain as well as the Sonoran Desert in Arizona and a few other areas in the southern United States.

Facts about the Saguaro Cactus

The Saguaro cactus’ roots grow as long as 30 meters underground. Stems reach up to 20 meters and spines are 2 meters long.

One variant, the Champion Saguaro, can be as tall as 45.3 feet or 13.8 meters.

The Saguaro can live for as long as 150-200 years, but It takes its time growing. For example, it can take up to a century for the cactus to grow to 8 meters tall. One branch or arm can take 75 years to reach full length. Spines, though can grow up to a millimeter in a day. Although a cactus can survive with little water, the Saguaro grows faster when it receives more water.

The cactus’ flowers bloom at nighttime from April to May. Its edible fruit comes into season in June. Sanguaro seeds need pollinators such as fruit bats.Like other cactus plants, the Saguaro is designed to store as much water as possible when it comes. A single plant can hold water nine times its own weight.

The Saguaro Cactus and Its Ecosystem

This cactus is extremely useful to humans and animals living in the desert. Several species of birds including woodpeckers, owls, house finches and purple martins make their homes in the Sanguaro’s thick stem. Native Americans used the cactus’ ribs in building their homes. Today the Sanguaro is a highly protected species. Arizona state law forbids damaging or taking down this cactus. Even road and house constructions need special permission from the local government if there is need to cut down a plant.

The Saguaro in Film and Advertising

The Saguaro cactus with its broad, fork-like stems has become one of the most recognizable features of the American desert. It is recognized by a straight central branch flanked by several shorter arms. If there is one cactus everyone is familiar with, it is the Saguaro.

But the Saguaro is not as widespread as its over-exposure in the media would have people believe. The largest cactus in the world can be found only in very specific areas in the United States. Sanguaros are not native to Utah, New Mexico, Texas, Colorado and Nevada, and very few are found in California. It is not even seen in northern Arizona.