The dazzling white blooms of saguaros and showy yellow palo verde trees get lots of attention at this time of year — but the often underrated blooms of cholla and prickly pear cacti are putting on their own spectacular spring show.

Blooms range in color from bright red to yellow, pink and peachy hues.

Unlike wildflowers, these cacti can bloom abundantly even in years with little rain, and their flowers last longer than the single day for individual saguaro blooms.

FLOWERING FACTS

“Most prickly pears and chollas bloom every year,” said John Wiens, nursery horticulturist at the Arizona-Sonora Desert Museum west of Tucson. “They are not as dependent as leafy plants on rain for their bloom, as they store moisture within their stems.”

“Flowers usually last two to three days,” Wiens said.

He said cholla and prickly pear are closely related.

“They are widespread in our region,” Wiens said. “Locally, there are at least five species of prickly pear: sprawling, Engelmann’s, pancake, Santa Rita and long-spined. And there are nine species of cholla: buckhorn, staghorn, cane, jumping, desert Christmas, pencil, teddybear, tree and Kelvin.”

Some of the species bloom from late March to late April, others from mid-April to early June, and some produce flowers in June and July.

Wiens said cholla and prickly pear have “a neat evolutionary adaptation called reactive stamens.”

“As a pollinator, usually a bee, goes into the flower to retrieve nectar, the stamens — stalked pollen-producing structures — draw inwards, enveloping the insect,” he said. “It comes away from the flower covered with much more pollen than if the stamens were static. This happens in under five seconds.”

If the process of pollination is a bit complex, the eventual outcome is dazzlingly evident: bright, colorful blooms.

Contact reporter Doug Kreutz at dkreutz@tucson.com or at 573-4192. On Twitter: @DouglasKreutz