Mandevilla

This vigorous climber can reach 3m (10ft) tall or more, with twining stems clad in glossy evergreen leaves. In summer, it produces an exotic display of large trumpet flowers. Depending on the species, these may be red, pink, white, cream or yellow. Newer cultivars have been bred to be more compact.

Originating in tropical climes, this tender climber needs plenty of warmth (at least 21°C/70°F), humidity and bright light. During winter, it likes drier conditions and slightly cooler temperatures of 10–15ºC (50–60ºF).

Avoid low temperatures – if kept below 21ºC (70ºF) in spring and summer, mandevillas may fail to flower, while winter temperatures below 10ºC (50ºF) may cause their demise. They dislike shade, dry conditions in summer, and overwatering in winter.

Four mandevillas have an RHS Award of Garden Merit, which means our experts recommend them as excellent performers. They are: white-flowered Mandevilla boliviensis, pink M. splendens and M. × amabilis ‘Alice du Pont’, and fragrant M. laxa.