Have you ever wished you could ‘splash’ colourful flowers all over your garden, as if with a magical paintbrush? Mandevillas can do just that, providing bold, tropical colour and looking fabulous for most of the year with minimal effort.
Mandevilla (sometimes called Dipladenia) is a lush, tropical climber that flowers flamboyantly all year round In warmer climates. Hardy and versatile, it flowers in shades of deep burgundy, scarlet, through all shades of pink and white. It is great in large pots where it can bring an instant lush, tropical look to poolsides and outdoor entertaining areas. Give it a sunny position for best flowering, a rich, well drained soil and plenty of moisture during the growing season. Originating from tropical South America, it loves a Cairns or Brisbane climate but will grow well as far south as Melbourne if given a warm position and shelter from frost. It is likely however, to stop flowering in winter in cooler regions.
Training your mandevilla
The mandevilla is naturally a climber but can be pruned into a compact bush. If untrained, it will grow upward to a certain height and then the long runners will tumble downward like a fountain, so a decision needs to be made whether to train it as a bush or as a climber. Support at the base of the plant by staking it when it is young will help it develop a solid ‘trunk’ and give it a bushy or shrub-like habit. If you want your mandevilla to be a climber, provide it with a trellis or plant it near a fence or pergola and wind the long tendrils onto the structure as it grows.
Tip prune non-climbing plants regularly to promote bushiness. Cut back thoroughly in late winter or spring, when flowering is lightest. Even mandevillas trained as climbing plants will do best if pruned annually.
Mandevillas have a tuberous root system which makes them hardy during dry spells but which also makes them susceptible to root rot in boggy conditions, so make sure they have good drainage and don’t overwater during winter. Apply a generous layer of mulch to conserve water.
Keep mandevillas well fed with an application of Searles Robust in October and again in April. Alternatively, year-round feeds with Searles Flourish — fortnightly in summer, monthly in winter, will keep plants healthy and promote flowering.