Mention bougainvillea to most people, and their first image is likely of sun-drenched plaster walls decorated in neon tropical colors. From the coast to the desert to the lush tropics, their exotic feel declares, “I love warm weather!” In the relatively small family Nyctaginaceae, confetti perhaps the most famous member, with Miracles (four hours) and Abronia (sand verbena) is the second species. With bougainvillea, the color is created by papery bracts surrounding a small white flower, which is the true flower. The flowers bloom cyclically: as a new growth matures, a cycle of blooms begins, repeating over and over again over the course of a long, hot season. Learn the basics of growing bougainvillea here.
Overview of paper flowers
Area: 9–11
Light: Minimum half-day sun (4–6 hours); full sun for best color
Land: Good drainage
Humidity: Water deeply, infrequently
Fertilizer: Minimum unless in container
Provide enough heat and sunlight for bougainvillea
Many of the wonderful species and hybrids we enjoy today originated in tropical South America, especially Brazil, Argentina and Peru. They have been introduced throughout the tropical and subtropical world, and hundreds of cultivars have been selected from Mexico to Thailand. The fact that they thrive in the Southwest is no surprise. Bougies are not only heat tolerant, they like it, and even in our deserts the reflected heat from stone and concrete is well received. They will flower readily on a half-day of sun, but full sun will bring out their most vibrant colors. Once established, they require minimal watering, preferring occasional deep soakings and considerable drying in between. Fertilizer is rarely needed unless grown in containers.
They come in all shapes and sizes.
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Bougainvilleas come in tall, hardy forms as well as more manageable shrub forms. As climbing shrubs, they do not twine or cling; instead, they cling to the frames of neighboring plants with their large thorns. This can make pruning difficult, requiring gloves and long sleeves. A sturdy structure or trunk is essential if height is desired. Shrub forms are more user-friendly in smaller settings. Additionally, bougainvilleas will also thrive in containers and hanging baskets. This makes them easy to move out of harm’s way into garages or other protected settings when frost threatens. However, it is important to note that with their limited root zone, they will always need regular watering and fertilizing in containers.
Be mindful of colder temperatures and protect as needed
Bougainvilleas are generally recommended for harsh weather in Zones 9–11. In the warmest parts of the Southwest (Zones 10 and above), they grow quickly and carelessly, with large varieties easily reaching the eaves of a house (and higher) and spreading freely over walls and structures. Below Zone 10, where there is a constant risk of frost damage in winter, they will often grow into hedge-height shrubs. On nights below 30°F, the shrubs should be covered with a cloth (sheets, blankets—never plastic!) to prevent damage. Leave the mulch on during cold weather to retain heat during the day.
If a hard freeze does occur, most can still tolerate roots at around 26°F. The stems may die back to the base and require rejuvenation pruning in the spring. Wait until new growth begins to appear on the lower stems to know how far to prune. Even then, be aware that late frosts can damage these new shoots.
The most beautiful varieties of bougainvillea
Varieties for this group of plants are plentiful, with just about every color except true blue. Here are some of my favorites:
Discuss this and any other gardening topic on our Southwest Gardening forum.
For more plants that thrive in hot weather:
Heat loving plants
Plants for Hellstrip
Plants for hot and dry areas of the garden
Find more information about gardening in the Southwest here.
Dan Johnson lives and gardens in Denver, Colorado and Tucson, Arizona. He is the associate director of horticulture at the Denver Botanic Gardens.
Photo: Dan Johnson
