There is some confusion over just which states comprise the southwest United States. Arizona and New Mexico seem to be on everyone's list. According to the U.S. Geological Survey, however, the southwestern United States includes extreme western Texas (west of Amarillo), Colorado, New Mexico, Arizona, Utah, Nevada and California. There is a lot of diversity, both in climate and vegetation in the southwest. Generally, anything growing in this region must be able to thrive in dry conditions.
Also called soapweed, the yucca flower is New Mexico's state flower. This member of the lily family is an evergreen shrub that grows to 3 feet in height and boasts a very long root system. It blooms in May and June with white, drooping flowers. The soapweed is a highly adaptable plant and thrives in the deserts of New Mexico where temperatures can get to below zero in the winter and as high as 106 degrees F in the summer. Grows best in sandy soils, but it has also been found doing fine in deep clay in Texas.
Saguaro Cactus Blossom
Looking at the giant saguaro cactus, it's difficult to believe that it could produce anything as pretty as the saguaro cactus blossom. Occurring mostly in the Sonoran desert, this is Arizona's state flower. The saguaro blooms at night with 3 to 5-inch, mostly white flowers. Pollinators not only need to be nocturnal, such as the bat, but quick as well for the flowers last for only one day.
Crickets destroyed most of the food crops in Utah between 1840 and 1850, causing a massive food shortage. It was the root of the sego lily that sustained people during that decade so, in 1911, it was named Utah's official state flower. Sego lily grows to 8 inches in height and blooms with white, purple or yellow, short-lived flowers during the summer. It prefers sunshine and dry, sandy soils.