Container Growing a Bougainvillea
Bougainvillea were first found in Brazil, but have since become a favorite colorful addition to tropical and temperate gardens around the world. Bougainvillea can be container grown, used as a hedge, trained up a climbing trellis, trimmed like a tree or pruned as a bonsai. If you live in a cooler climate, consider container growing your bougainvillea so you can move them inside in the winter.
Step 1 – Choose a Container
Bougainvillea can grow in any container that drains well, from terracotta pots to hanging baskets. Choose something that suits the look you want and is flexible to be moved inside if you need to to protect your bougainvillea from the cold. Bougainvillea like moist soil but not standing water. If your container has some kind of saucer under it, remove it.
Step 2 – Choose a Potting Mix
A standard potting mix will work fine. The characteristics to look for are good drainage, aeration, a small measure of water retention, and plenty of nutrients. Bougainvillea likes a pH between 6.0 and 6.5. If you use a hanging basket, a layer of sphagnum moss on the exterior can be a lovely soil alternative visible from below. Just remember to keep it moist.
Step 3 – Water and Fertilizer
Keep the soil in your pot moist, but avoid standing water. Standing water will result in root rot. Bougainvillea will often bloom best when kept a little dry.
Bougainvillea do like nutrients. Fertilize with a standard fertilizer to encourage blooms. However, minimize fertilizer use right after repotting. At that time the plant needs to focus on growing roots and recovering from the shock of being moved rather than on growing flowers.
Step 4 – Locating Your Container
Feel free to put your bougainvillea in the sun. The plant does quite well in bright light. However, if it has been raised in the shade to date, transitioning it gradually to full sun will keep it in better health. Your bougainvillea will do best when getting at least 4 hours of sun a day.
If the container is to sit on the ground, provide something underneath to keep the drainage holes off the soil below. If allowed to stay in contact with the ground, your bougainvillea will send roots through the drainage holes into the ground. When you lift the container, the roots will break and your bougainvillea will loose important feeder roots. Propped up on bricks or a few pieces of wood, the roots will be stopped at the air layer and remain in the pot. Propping will also improve drainage. If placed on a solid surface, make sure you provide room for your pot to drain somehow.
Make sure that your container won't be too heavy to move. A layer of styrofoam packing peanuts at the bottom will decrease the weight and keep debris from slipping out the drainage holes.
Step 5 – When to Repot
Bougainvillea blooms best when it is root bound in a pot. The delicate root structure is best when dense. So don't repot too often and increase the size of the container in small increments. Be careful when removing your bougainvillea from its pot. The roots and the connection between the vines and the roots are delicate. Keep the root ball intact and resist root pruning or loosening the root structure. These will just damage your plant. If you want to decrease the size of your plant, just prune.