Bougainvillea is a stunning flowering plant that can bloom almost constantly under the right conditions. These tropical natives actually thrive on neglect at certain times of the year. For success, choose a variety of bougainvillea -- vine, shrub or miniature plant -- that is suited to your growing environment. Most bougainvilleas are hardy in U.S. Department of Agriculture zones 9 and above; in cooler climates, move them indoors for the winter. Learning about your bougainvillea's needs can keep it healthy and flowering for three to six months a year --maybe even longer in warmer climates.
Provide your bougainvillea a well-draining, acidic soil that has a pH between 5.5 and 6.5. When growing in a pot, use a soil-less mixture for best results.
Grow a potted bougainvillea in a small, light-colored container -- the plant performs better when its roots are crowded. Don't repot your bougainvillea very often; when you do, use just a slightly larger pot and don't prune its tender roots. Elevate the pot above the ground so the roots don't grow out the bottom and into the ground.
Plant or place your bougainvillea where it will get at least five hours of direct sunlight every day. Too much shade will reduce blooming and affect the colors of the bracts, the papery "petals" around the bougainvillea's tubular flowers.
Water your bougainvillea sparingly. It's a drought-tolerant plant that doesn't need much water once it's established. Let it dry out between waterings -- a little wilting is the sign that it's time to water -- then water it thoroughly, recommends Bougainvillea Growers International.
Prune your bougainvillea at any time of the year to shape it, control growth and encourage flowering. Bougainvilleas flower on new growth, so pinch off the buds at the end of stems every three to four weeks, leaving two side buds. Let those grow until each one can be pinched back to two buds. Repeat once more before letting the bougainvillea form flower buds; this will make your plant bushier.
Fertilize your bougainvillea every two weeks during blooming season with a water-soluble fertilizer used at half strength, or with full-strength hibiscus fertilizer. Feed the plant monthly when it isn't flowering. Don't fertilize it during winter dormancy.
Bring your potted bougainvillea inside before the first frost if you live in a cooler climate. Cut it back by half before bringing it indoors. You can keep it actively growing by placing it in a warm, sunny spot, or allow it to go dormant by placing it in a cool, dark area -- such as a basement or garage -- where temperatures will stay above freezing. Water a dormant plant just once a month and don't fertilize it. After two or three months, place the plant in a sunny window, then move it outside when temperatures regularly stay above freezing.
In warm climates, you can give your bougainvillea a hard pruning in late winter, just before new growth begins.