A spectacular tropical flowering vine, mandevillas have large, glossy green leaves and trumpet-shaped flowers in shades of pink, red, purple or white. They are native to Central America and are now widely grown in warmer areas. In zones with temperatures that fall below the 50s, mandevillas are grown as annuals. Their fast-growing habit makes them ideal for use as a summertime privacy screen. Like most tropical plants grown in colder areas, it is possible to overwinter them indoors, but they must be cut back severely.
Mandevillas are a twining type of vine. This means that they support themselves by spiraling around their supporting structure. In their native habitat, they twine themselves around trees in a parasitic type of relationship. You can support a mandevilla with a single sturdy pole, which it will climb nicely. They can also be planted along an openwork fence, such as a wire-type of cyclone. The vines will twine around the openings in the fence and quickly provide privacy.
Mandevillas are heat-loving tropical plants. Position them in a sunny spot on or near a concrete or stone patio, terrace or walkway. The mandevilla will thrive in the reflected heat from the stonework and will produce copious amounts of flowers. When temperatures dip down below 65 degrees Fahrenheit, mandevillas stop blooming. They will not survive winter temperatures below about 55 to 60 degrees Fahrenheit. Overwinter your mandevilla indoors in temperate zones.
These twining vines are fast growing and can put on upwards of 10 feet of new growth in a single growing season. Because it is so fast growing, mandevillas need regular but moderate doses of fertilizer. Feed them every week with water-soluble fertilizer specially formulated for blooming plants, mixed at half the strength recommended by the fertilizer manufacturer. Fast-growing plants also require a lot of moisture, but mandevillas do not like wet feet, so ensure that they receive adequate drainage. Water them when the soil feels dry to the touch about a half an inch below the surface. Be sure to water them thoroughly so the water drains out of the bottom of the pot.