Picture an estate on a Caribbean island or a hidden garden behind a funky Key West home. Most likely you'll envision bougainvillea enveloping the walls. This bright tropical South American vine was named for Admiral Louis Antoine de Bougainville, who sailed around the world in the mid-1700s. Bougainvillea, a member of the Four O'clock family (Ncytaginaceae), is a woody, thorny, evergreen tropical and subtropical woody vine. Bougainvillea can be allowed to cover a wall, trained as bushes or kept in large containers.
Bougainvillea's vibrantly colored "flowers" bloom all summer. Like poinsettia, these "flowers," however, are really modified leaves known as bracts. The bracts surround the plant's tiny yellow-white tubular flowers. Bougainvillea's bracts come in a wide range of colors: pink, purple, cream, orange, crimson, white and yellow.
Some of the most popular varieties are "California Gold" (golden yellow), "Barbara Karst" (bright red), "Juanita Hatten" (dark pink), "Sundown" (apricot), "Surprise" (pink-white) and "Vickie" (pink or white, with variegated leaves).
There are several species in the genus Bougainvillea, but only three (B. spectabilis, B. glabra and B. peruviana) are popular with gardeners. There are many hybrid species, including "Orange King" and "Jamaica White."
Cuttings and Transplants
Bougainvillea is easy to grow from cuttings. Tender shoots up to six inches long should be placed in a perlite and peat moss mix and kept moist and warm.
Transplanting is a more delicate operation, as the bougainvillea's roots are quite fine and easily torn. The plant will respond better if it has been fertilized a few weeks ahead of time and kept well watered. You can expect some leaves to drop immediately, but the plant will return to its vigorous growth cycle.
Bougainvillea can easily take over an entire wall. Don't be afraid to trim; it responds well to pruning and can even be trimmed into a hedge. Keep suckers pruned from the bottom of the plant to encourage the top to grow. The best time to prune heavily is late fall, when the flowers have stopped blooming.
How to Grow
Bougainvillea requires full sun for the best growth and flowering. While it would like well-drained soil with a pH of just over 6.0, bougainvillea will grow in almost any soil as long as it isn't constantly wet. Fertilize lightly with 10-10-10 in early spring and midsummer.
Bougainvillea can survive outside in USDA zone 9 if protected, but prefers zone 10. Anywhere farther north, bougainvillea is considered an annual, though it can be grown as a houseplant or as a container plant.
Bougainvillea will need a five- to 10-gallon clay container to survive outdoors. The large clay pots don't retain water and won't stress the plant. If you want to use a hanging basket, choose one that is 12 inches in diameter.
Both container and hanging plants will need at least a half day of full sun. Any light, well-drained potting mix will do. To make your own, mix three parts peat moss, two parts perlite and four parts of well-rotted pine bark. For every five gallons of this mix, add in one-half cup of Osmocote and two tbsp. of 19-5-9 slow release fertilizer.
Diseases and Pests
Bougainvillea is incredibly tough, though in adverse conditions it may develop fungal or bacterial leaf-spot diseases. Aphids, scales and mealybugs occasionally will attack, but usually only on weakened or non-thriving plants.