Bougainvillea Bonsai Care Guide

As Brazilian native species, Bougainvillea need high temperatures and full sun to produce its flowers. During the growing season, it will need to be placed outside in a sunny position. However, this species will not survive a winter in a temperate region like the UK, particularly with its dependable rainfall.

As an outdoor plant, Bougainvillea bonsai must be taken indoors during the autumn to a sufficiently lit, cool room and temperatures not dropping below 10 degrees C. 

As an indoor plant, Bougainvillea needs to be kept in a sunny and warm room, ideally a heated conservatory. Otherwise, supplementary lighting and heating must be provided.

Bougainvillea bonsai should be watered considerably when the soil feels dry on the surface. Be careful not to achieve constant wetness of soil as this will affect the plant with fungal problems, root rot or worse. When the buds start to develop in Spring, you can increase the amount of water to maintain the soil moistness. For a very dry indoor atmosphere misting the leaves is advised. 

Across the growing season use an organic solid feed once a month. Liquid feed is usable once a week during the growing season. Every two weeks during winter.  

Pruning your bonsai is important not only to create or maintain an aesthetic style but to also ensure optimal health. In the autumn and winter prune twigs and branches. Shoots should be cut after flowering leaving just two leaves on each. This species can still bud from older wood after a robust pruning. Don’t overly pinch or trim during the summer if you want your Bougainvillea to flower. 

Bougainvillea can wired although the overwhelming majority of its shaping can be achieved through pruning. Young shoots and twigs are responsive to wiring, older branches less so. We recommend using wires with a thickness that matches the thickness of the branch: if the wire you choose is too thick you will damage the bark. If it is too thin, it won’t be effective.

Repotting your tree is an important way to provide a fresh and suitable soil mix and ensure appropriate root health. A small Bougainvillea should be repotted every two to three years. A larger Bougainvillea needs repotting every three to five years. This species has delicate roots so take extra care when repotting.   

Trees that are ready for repotting will require root pruning, a suitable new pot and appropriate soil mix.

When repotting, do not cut back the root mass by a large amount, and choose a well-draining soil mix that has a neutral or slightly higher PH value of 5-6 but not over 7. We tend to use a mixture of different speciality bonsai soils on our trees. Every species is different so please contact us for free soil-mix advice or to take advantage of our repotting service.