One mark of tropical climates is often the carefree, hot-weather-worshiping flowers that cover everything in lush splendor. The bougainvillea vine is the queen of sultry climes, producing ruffly blooms in vivid shades for a spectacular effect. Grow bougainvillea outdoors in warm weather zones, or as an indoor plant.
An evergreen vine, the bougainvillea belongs to the 4-O'Clock family (Nyctinaginacea) and hails from South America. Leaves are shiny and oval-shaped, and vines reach heights in excess of 30 feet. Blooms are composed of modified leaves called bracts that provide the showy pink, orange, yellow, red, purple and elegant white ruffles with the true, demure white flower just visible in the center.
Don't plan to grow these hot-weather lovelies in the ground in any zone outside of 10 or 9, and even in zone 9 they need protection. When grown naturally in tropical climates, the bougainvillea prefers 65 degree Fahrenheit temperatures at night and up to 100 degrees during the day and plenty of natural sunlight. Acidic soil in the 5.5 to 6.0 pH range is best, with just enough water to keep soil from drying out. Avoid over-watering. Allow up to 9 feet between vines to allow for vigorous growth and spread.
Container and Indoor Plants
In cooler winter zones where summer evening temperatures stay above 60 degrees, you may be able to grow the bougainvillea vine in a container. Use rich, organic soil and choose a gallon-sized or larger container with a drainage hole in the base. Provide a trellis or structure behind the container to support the vines. Grow bougainvillea indoors in clay pots, which keep the soil on the dry side, and provide plenty of natural light with minimal watering.
A phosphorus-rich, slow-release fertilizer should be added to the soil per manufacturer directions at planting time. Add additional fertilizer mixed with the top soil every three months throughout the growing season but avoid over-fertilization. Flowers appear on new growth, so encourage more blooms by pinching back to one or two buds on each stem. For in-ground plants, reduce the size and provide shape by cutting back 1/3 of the oldest growth yearly, as well as any sickly or poorly performing sections.
There are three notable species of the bougainvillea vine. Bougainvillea spectabilis is Guam's territorial flower. With claw-shaped thorns, it sports blooms of red, purple and vibrant pink. B. glabra is notable for triangular-shaped pink, purple and white bracts and grows prolifically in Hawaii. As the name suggests, B. peruviana was discovered in Peru and grows in a less-structured form than the other species. Thorns are smaller and straight, blooms are typically in the pink family, and this species responds well to pruning.