Queen of the Night Bloom Watch

This mysterious and majestic flower blooms for only one night a year.

For 364 nights out of the year, the Night Blooming Cereus cactus (Peniocereus greggi) looks like a pile of dead, gray vines. However, at the beginning of the summer, the Southern Arizona heat triggers these ordinary mundane cacti to simultaneously bloom with beautiful flowers, which are commonly referred to as The Queen of the Night. These flowers only last a single night, and begin to wilt as soon as the morning sunlight hits them. This mass bloom event occupies a special place in the hearts and imaginations of many in Southern Arizona, and has done so for millenia.

Where Can I Find The Queen of the Night Flowers?

The Night Blooming Cereus, although they can be found in warmer climates all over the world, is native to Southwestern North America. Today, Tohono Chul Park, located in Northwest Tucson, is home to the world's largest collection of these cacti. Every year, people wait anxiously and patiently for Bloom Night, when all of the park's cacti reveal their blooms. Pima Prickly Park on River Road also contains a significant collection. Additionally, the Night Blooming Cereus can be naturally found in sandy soils, on the banks of washes, or on hill slopes; shaded by desert shrubs or by trees. Each cluster of cacti blooms simultaneously. Blooms at different locations will most likely happen on different nights, so be sure to pay attention to the update system for the particular location you're planning on going to.

Beautiful queen of the night cactus arizona in full bloom

How Do They Know When the Flowers Will Bloom?

In short, there is no precise way to determine when the Queens of the Night will make their appearance. However, Bloom Night typically happens sometime from Mid-June to Mid-July, but that's as precise as it gets. Shortly before blooming, the cacti will sprout buds, which eventually become the flowers. Tohono Chul publishes updates via an email newsletter, as well as on social media, about when they are expecting the flowers to bloom. They usually aren't able to predict that the blooms will occur until the day of, so you may only have a few hours' notice. 

Why Do They All Bloom At Once?

The Night-Blooming Cereus is unable to self-pollinate, therefore, all of the plants within a particular area have to bloom at the same time, to provide the greatest chance for cross-pollination. Scientists think that the cacti use some form of chemical communication to synchronize the blooms!

Does the Bloom Have Cultural Significance?

In addition to being a highlight of the summer for many in Southern Arizona, the bloom also holds a significant place in Tohono O’odham storytelling and heritage, owing to its mysterious nature. The Queen of the Night has also inspired songs, paintings, photographs, and a perfume (the flower is known to be highly aromatic). 

What Do I Need To Know If I Go See The Bloom?

In order to receive updates on the Queen of the Night and to be notified when they are blooming, sign up for the Bloom Watch newsletter on Tohono Chul's website, and follow their social media accounts. When you're notified that the bloom is happening, make plans to arrive at either park between 5 PM and dusk. Be sure to bring a flashlight, a camera with a flash, plenty of water to drink, and wear closed-toe walking shoes. The flowers start blooming around 5 PM, and are usually in full bloom by dusk. Once there, prepare to be amazed by the sights and smells of the arrival of the Queen of the Night. Tohono Chul Park is open to the general public from 6 PM - 10 PM on the night of Bloom Night, and admission is $5.

queen of the night flowers blooming in Marana Arizona desert with orange, yellow and pink sunset

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