Bougainvillea is a thorny, tropical vine native to Brazil, but grown in many parts of the world. It is most well known for its impossibly bright colored flower bracts, ranging from yellow-orange to hot pink to intense, deep purple. Under ideal conditions, bougainvillea blooms from April until late fall. As a tropical plant, it loves full sun and hot weather, and should be protected from windy locations. Also, the roots should not be disturbed - use extreme care when repotting or transplanting.
Water your bougainvillea and let it become moderately dry between waterings. If you let it dry out completely, it may shed all of its buds and flowers. Overwatering may also cause bloom or leaf drop, leaf discoloration or root diseases. Avoid leaving the plant out in the rain or letting leaves remain wet for a significant period of time. Letting the soil become slightly dry and misting the foliage with clean, tepid water is a good formula.
Feed your Bougainvillea every other week, alternating between water soluble 20-20-20 and 10-30-10 (bloom food). Leaf yellowing may be helped by adding chelated iron or magnesium sulfate (epsom salt) to the fertilizer routine. Please note: leaf yellowing may also be caused by lack of sunny weather and is somewhat common on purple varieties.
Pinching back is the key to a well-branched, full-blooming bougainvillea. It blooms on new growth, and more branches mean more blooms, so pinch back new shoots as you would with a fuchsia. Please note that DOUBLE FLOWERED BOUGAINVILLEAS do not shed their old flower heads, as single-flowered varieties do. They should be cut off after they fade, to keep the plant looking good.
In late September, or whenever the weather starts to change and there is a chance of frost, bring your bougainvillea indoors to a sunny window or greenhouse. Cut it back, reduce fertilizing and treat it as a foliage houseplant. After a dormant winter, it will start to grow and bloom again in spring when the conditions are right.