Rincon Institute
Ecology in Focus — Saguaro Blossoms
Not long ago I sat on the beach at Rocky Point with a 19- year-old friend of mine. As we watched a group of porpoises playing not far from shore, she commented on the miracles that the ocean beheld. I replied, “yes, almost as many as the Sonoran Desert.” She looked at me incredulously and said, “there aren’t any miracles in the Sonoran Desert.”
At first I was flabbergasted that a native Tucsonan did not realize the richness of life that ekes out an existence here. But the more I thought about it, the more I realized that many of the miracles of the Sonoran Desert are ones that are not always obvious unless one takes a moment to seek them out. Take the blossoms of a Saguaro for example.

saguaro_blossomEach April and May, the sentinels of the desert, the Saguaro cacti (Carnegiea gigantea), begin to put forth their blooms. From a distance the buds and resulting flowers give even more personality to these desert characters because they resemble fingers (on the arms of the cacti) and hair (on the top).

In fact, the blossoms of the Saguaro are miraculous organs of reproduction which are responsible for the persistence of the plant.

The flowers are sturdy white blooms set atop the arms and tops of the cacti and are, in the words of Edward Abbey, most assuredly “unpluckable.” This inaccessibility for humans, however, does not stop the primary pollinators from relishing the nectar buried deep with the flower. The flowers open at night and tend to stay open through the early afternoon. Its white color makes it easy for nocturnal pollinators (especially bats such as the lesser long-nosed bat, Leptonycteris curasoae) to see it in the dark. Its daytime flowering attracts other pollinators such as White-winged doves and great numbers of bees (including Diadasia opuntiae). Hundreds of blooms can flower on each individual Saguaro and each pollinated flower matures into a 3 inch- Fruit which can contain up to 2000 seeds. The fruits ripening is perfectly timed — occurring just before the monsoon season and seeds which have been dispersed by Gila Woodpeckers, Whitewinged Doves, and other birds, germinate within 5 days of a rainstorm.

saguaro_cactiOnce the seeds have germinated the harsh existence of the Saguaro begins and, as we can see by looking around us, very few make it into mature cacti. But still, thanks to the blossoms, the Sonoran Desert continues to contain these quiet giants which set it apart from any other biome in the world. When you examine a Saguaro blossom up close, and see and hear the buzz of activity within it and think of all the effort and luck that goes into creating a new Saguaro, it is easy to see why these cacti really are miraculous!