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Night-Blooming Cereus at Tohono Chul Park in Tucson, Arizona

Two Night-Blooming Cereus

Two stunning blossoms of the night-blooming cereus made their debut at Tohono Chul Park in Tucson, Arizona, on July 10, 2014. Photograph by Susan E. Swanberg

Each year Tohono Chul Park, a nonprofit botanical garden and nature preserve in Tucson, Arizona, opens its gates for the evening so the public can observe one of Nature’s most remarkable events—the blooming of Peniocereus greggii, the night-blooming cereus.

The cactuses bloom from late May to early July. Blossoms of each Peniocereus greggii population open in nearly synchronous batches or “flushes,” beginning on a warm summer evening, shortly before sunset. The flowers continue to bloom throughout the night and are pollinated by hawk and sphinx moths, members of the family Sphingidae. As they bloom, the flowers emit an intoxicating fragrance. By the following morning, the flowers fade.

Two Night-Blooming Cereus

Cereus blossoms showing the thin, spindly cactus stalks from which the magnificent blooms grow. Photograph by Susan E. Swanberg

In previous years, the majority of the night-blooming cereus at Tohono Chul Park bloomed simultaneously during the course of a single evening. This year, however, there was a split bloom, with some of the plants blooming on July10 and others blooming on July 11.

Related to the Saguaro, Carnegiea gigantean, the night-blooming cereus, also known as “The Queen of the Night,” is a Sonoran Desert native. Unlike the flowers of the mighty Sahuaro, the night-blooming cereus buds grow from an inconspicuous, dry-looking cactus. The tuberous root of the plant provides the energy needed to produce the spectacular summer blossoms.

Don’t miss this event next year. Tohono Chul Park has the largest private collection of the cactuses in the world.

Night-Blooming Cereus bud waiting for the right moment to bloom

Night-blooming cereus bud waits for the right moment to open at Tohono Chul Park on July 10, 2014. Photograph by Susan E. Swanberg

The End

© 2014 by Susan E. Swanberg

Previously published in the Green Valley News, Green Valley, Arizona