Bougainvillea Bonsai Care Guide
This flowering vine is well-suited to bonsai and is favored for its large, bright blooms. As a garden plant, it is versatile and trainable – used as hedges, ground cover, container plants, or decorative growth on latticework or walls. Native to South America, bougainvillea is commonly seen throughout the warmer climates in the United States and thrives in humid conditions.
There are many varieties of this subtropical, with Bougainvillea brazilinensis 'Pink Pixie' being a particularly good choice because of its harder woody trunk. Other suitable cultivars include Bougainvillea buttiana 'Golden Glow' (yellow fading to apricot), Bougainvillea glabra 'Snow White' (white), and Bougainvillea glabra 'Magnifica' (rose pink). Check out DallasBonsai.com for our seasonal selection of Bougainvillea bonsai.
The woody, gnarled stem of this popular plant makes it especially good for growing as a bonsai. The "flowers" are not actually flowers – rather they are bracts, leafy protective scales that surround the tiny white trumpet-shaped flower in the center.
Available colors include white, red, orange, pink, yellow, and violet. The branches of most varieties do have sharp thorns of varying lengths so care must be taken when trimming and pruning. Flowering will normally occur throughout early spring but may happen at other times of year as well.
The ideal temperature for this species is between 70-85 degrees F during the day and 60-70 at night. Bougainvillea can be kept as an indoor bonsai as long as it gets plenty of sunlight, and should preferably live outdoors during the spring and summer. Full sunlight is best for outdoor plants.
We recommend bringing your Bougainvillea indoors during cold winter weather dropping below 30 degrees to ensure safety and survival.
The Bougainvillea is drought-resistant and does not tolerate over-watering. While establishing the plant, water routinely to help the root system develop, then decrease to only when needed. The soil should have good drainage and once established the plant only needs sparse watering.
If there are few leaves but the plant has some color you may be under-watering. If there are plenty of leaves but not much color, it's possibly over-watered.
Flowering can be encouraged in summer by allowing the plant to dry out and wilt for a few hours, then watering normally again.
A low-nitrogen fertilizer should be used in the spring. A blend higher in K than N will help encourage blooming. Soil should be acidic – this can be accomplished by adding in some azalea fertilizer.
Other recommendations include supplementing with iron to intensify colors and increase bloom production and routinely administering slow-release fertilizer in a 6-8-9 ratio.
Bougainvillea take very well to training and can be formed into almost any of the bonsai shapes due to their ability to grow vertically or horizontally. Cascade, informal upright, and twin trunks are especially good choices. Try grooming one long, side-growing limb with multiple blooms for a dramatic effect.
Pinching off of growth should be done at a point slightly shorter than you want the finished length because blooms will appear at the site of removal. Removing the tips after each blooming cycle will encourage the growth of multiple new shoots, thus increasing ramifications.
To thicken branches, remove all blooms but do not prune the branch. When wiring, keep in mind that the branches of this tree are brittle so care should be taken not to wrap too tightly. When pruning, seal all cuts with wound sealant / pruning compound to prevent rot – if any rot is detected it must be removed completely.
This bonsai is easy to propagate from cuttings. Take a soft or hardwood cutting of 2-8", making sure there is at least one set of leaves. Make a wound in the bottom of the bark and plant in a container of sandy soil (rooting hormone is optional but recommended). Water and cover with plastic to retain moisture until new growth begins appearing.
This should be done in springtime every two to three years, taking care not to break the fragile roots off the plant. Bougainvillea love to be bordering on root-bound so be judicious in root pruning, removing only woody outliers and retaining as much of the fibrous root system as possible. Repot in a container that will hug the root ball as closely as possible while still allowing some soil for watering. Use a well-draining soil mixture like the Fujiyama bonsai soil mix.
Insects/Pests & Diseases:
While this bonsai is relatively pest and disease resistant, it can suffer from attacks of aphids, caterpillars, or snails. Treatment is not usually needed.
It can also be prone to fungal infection, which can be avoided with preventative fungal spray and monitoring the plant's humidity exposure, adjusting if necessary.