There is scarcely a soi on this island where you will not find the plant decorating the roadside; indeed in many places, it has adapted itself to highly unpromising conditions. The road chiseled through the hills between Karon and Kamala, for example, has self-sown bougainvilleas everywhere, and though they are frequently cut back, they continue to add a splash of colour to the rocky hillsides.
They seem to do extremely well on this island, even better here than in their much-vaunted Mediterranean setting, where the cold winters can seriously hamper growth. In Andalucia, I tried to grow them many times before one finally took off and prospered, Once established though, it grew into a huge bush whose spiny tentacles embraced the entire balcony. And that is typical of bougainvilleas: they are very tenacious once the roots get a grip.
The bougainvillea is not native to either Europe or Asia. It hails from Brazil, where it was discovered by a French explorer by the name of – you guessed it – Louis de Bougainville. It quickly became a feature in European formal gardens, and as happens with popular plants, was soon being hybridized. Nowadays, there are no fewer than 300 varieties around the world, mostly bred from three South American species.
The true flowers are small, white and insignificant; the real display is provided by the clustered bracts, three to six in number, that encircle the flowers. These richly-coloured bracts are paper-thin, a trait which has given rise to the popular name of “paper flower”.
While the commonest colour is pink, many striking cultivars have been produced in a range of hues ranging from pure white through scarlet to deep crimson. Now there is even a chrome yellow cultivar. Orange-scarlet hybrids are especially attractive. Double varieties include a deep magenta one.
The attractive foliage has paired leaves which are often reddish green in colour when young. But be warned. As with so many tropical shrubs, the stems are armed with lethal spines. Bougainvillea is in essence a vigorous, woody vine with a naturally scandent habit (that is to say, it sprawls) and it will scramble without ceremony over any plants that get in its way.
Since the stems can reach several meters in length, the plant will need to be regularly pruned, unless you plan rapid cover for a large area of wall or trellis. However, it is well to remember that unlike a “true” vine, the bougainvillea produces no tendrils, so it may well need support.
Certainly, it does not object to clipping. Hard pruning after blooming will promote a bushier habit and more flowers. It is also good practice to pinch out the last half inch of new growth to encourage lateral sprouting below the tip. Because it tolerates pruning so well, the bougainvillea is often used as a hedge. The spikes will certainly help to repel would-be intruders. It can also be pruned into a standard.
The bougainvillea is quintessentially a sun-lover. For this reason, it flowers best in the dry season when the hours of sunlight are at their peak. Five hours a day are a minimum requirement. Give it too much water and too little sunlight and it will grow and grow without producing much in the way of colour. So just remember that it is less likely to bloom effectively in the monsoon when its root system is moist. And it will not need much watering in the dry season. A low maintenance plant? Most definitely.
So how does the bougainvillea rate? Highly for visual appeal, length of flowering period and general adaptability. It is accepting of dry conditions, has a high tolerance to salt-laden winds and is remarkably resistant to disease. Bougainvilleas should take from cuttings and will tolerate life in a pot, especially dwarf varieties such as La Jolla.
Some of the most spectacular specimens can be seen growing in containers in local nurseries. Often they have had different hybrids grafted on to the root stock and look spectacular in their multi-hued livery. Many are venerable – at least 10 years old – and may set you back several thousand baht.
The downside? Despite having a compact root system, the bougainvillea is a gross feeders and will take both nutrients and space from any plants in its vicinity. Its growth habit is unwieldy and invasive. It has vicious spines, and because it possesses no perfume, it will not attract butterflies.
But a tropical garden without a bougainvillea? Unthinkable… It does not deserve its botanical name of Bougainvillea spectabilis for nothing.
Patrick has been writing for ten years about gardening in Phuket and allied topics. If you have any horticultural concerns, please contact him at firstname.lastname@example.org or visit his blog at Wordpress: Green Galoshes.