Tropical vines that bloom throughout much of the year, bougainvilleas make excellent container plants for both the indoors or outdoors. To grow a lush bougainvillea that hangs over the sides of the container and produces prolific blooms for which it is known, adopt several cultural habits sure to encourage a thriving plant.
Place a bougainvillea in an area with at least six hours of direct sunlight each day. A sunny porch or south-facing window might be the ideal location. If placed outdoors, do not set the container directly on top of the ground. The roots can grow out the drainage holes and take root in the soil. A drainage dish or an elevated surface, such as a crate, underneath the pot works well.
Allow the soil to dry out between waterings, providing water only when the soil is dry to the touch about 3 or 4 inches deep into the soil. Bougainvilleas flower best when they are stressed. At each watering, apply enough water that it drips out the bottom drainage holes. Dump out the excess water that accumulates in the drainage dish to ensure the soil does not remain soggy. Bougainvilleas will recover more readily from dehydration than from over-watering.