Of course, small trees or bushy shrubs can perform a similar role, but they do usually need a fair amount of soil in which to spread their root systems. A few columnar foliage shrubs might do the trick; for instance the plant Thais refer to as cristina with reddish, young foliage, or dense, evergreen sai. Cristina is almost always seen here as a neat hedge or geometrical form and is remarkably tolerant of heavy clipping and shaping.
But vines generally offer the best backdrop. They certainly have several advantages over trees: they tend to hug walls – indeed many are self-clinging and will climb ever higher in search of sunlight. And although grape vines have notoriously deep roots with a maximum of six metres or more, most climbing plants do not require as much soil in which to thrive as shrubs or trees that possess a comparable density of leaf growth. After all, hanging on to existing supports does not expend nearly so much energy as their hosts are expending to create a rigid, woody framework.
Moreover, you can grow climbers in two ways: use them from the ground upward (the usual method); or, where the walls are effectively terraces with the gardens behind abutting the summits of these retaining structures, the vines can be planted on top and allowed to cascade gracefully down. Oddly bougainvillea – that maid of all work – has been employed in this capacity in one garden I know, with the result that the view along the road below is embellished with masses of pink, white and crimson blooms.
Other climbers that can trail and help soften the man-made outlines might include the shower orchid (congea tomentosa) which has a naturally dangling habit and blooms profusely on long, thin, pendant branches during the winter months. The strings of flowers are lavender in colour – hence its popular name of lavender wreath. It is native to Thailand, enjoys the full sun that the climate provides and can, like bougainvillea, be grown in almost any soil type provided it gets sufficient moisture.
Thunbergia grandiflora (blue trumpet vine) is anther sensible choice, a robust member of a large genus of flowering climbers with heart-shaped leaves and long, hanging clusters of mauve or white trumpet-shaped blooms. Easy to grow, it likes sun or filtered shade.
Other vines are climbers pure and simple. The real experts – known as lianas in the rainforests – are self-clinging with tendrils or modified leaves which can attach themselves to any structure, natural or man-made, that happens to be within reach. Indeed the wild varieties can be a handful, swarming all over canopy trees and in some cases strangling them.
Cultivated varieties are less invasive, but my garlic vine (mansoa alliacea), an ornamental evergreen, semi-woody vine, has wound itself around an adjacent tree in my garden and is now covering the upper branches with blossom. Extremely vigorous, this garlic vine has attractive lavender or deep pink blooms with a white throat which fade to a paler colour as they mature.
Naturally there are many other climber candidates: antigonon (coral vine), argyreia (elephant creeper) and pyrostegia (flame vine), all of which inch upwards by means of tendrils. But they will have to wait their turn to grab the limelight.
Patrick has been writing for thirteen years about gardening in Phuket and allied topics. If you have horticultural or environmental concerns, please contact him at firstname.lastname@example.org. Many of his earlier creative and academic publications can be found at Wordpress: Green Galoshes.