By Bonnie L. Grant
Bougainvillea produce flame licks of color on a vine that can easily be trained to a vertical surface. The brilliant hot pinks and evocative orange tones spice up the landscape in warmer zones. The plants are perennial in United States Department of Agriculture zone 10 but are more suited to containers and annual use in zones 7 to 9. Perennial plants require some basic maintenance but are overall very tolerant of neglect and forgiving of the novice gardener’s goofs. Learn how to prune a bougainvillea as part of its vertical training and to help increase the impact of this tropical plant.
The bougainvillea plant is native to Brazil and introduced to Europe in the 19th century. The famous Kew gardens were instrumental in the propagation and spread of the plants. Trimming bougainvilleas yields cuttings that were rooted and grown on for new specimens.
The startling colors of the plant are actually from bracts or modified leaves, not flowers as they appear. The best time to prune bougainvillea for cuttings is in late winter to earliest spring before new growth has flushed, but when bud nodes are swelling. There are now cultivars and crosses from several parent specimens that range in color, size and hardiness.
Pruning and trimming are two different things. Trimming establishes an outline and keeps a plant in a certain visual habit. Generally, trimming removes smaller material and leaves a certain silhouette.
Pruning is useful for training a plant and to remove old neglected branches. It is also the basis for the final adult plant’s scaffold. Trimming bougainvilleas helps keep the plant in an already chosen shape. This generally means tip pruning and light topping to minimize ranginess.
How to Prune Bougainvillea
Bougainvillea pruning for hedges is severe, but usually the plants are trained to trellises or other vertical supports and need minimal pruning in early spring to enhance growth. Young plants need to be pruned from the base to force thicker growth.
Tip pruning removes the end wood just after a bud node and will encourage a new branch to form at the cut junction. Remove dead wood as it occurs but severe pruning must wait until the plant is semi-dormant in fall or early spring.
Overall Bougainvillea Care
The vines need well-drained, yet moist, soil to thrive. Bougainvilleas are drought resistant and perform best if the soil is allowed to dry out between watering.
A full sun site is the best and they flower most when the temperatures are moderate with long cooler nights in spring. The plants grow well in a greenhouse or in containers. Just don’t forget to move them indoors when temperatures begin to fall, as the plant has little cold tolerance.
Plants grown indoors should experience annual bougainvillea pruning for maintenance and to keep them small enough for transitional movement and ceiling height.