Mandeville

Mandeville Family: Apocynaceae (dogbane family) Common names: mandevilla, pink allamanda Genus: Mandevilla Every so often a plant jumps off the page of a gardening magazine and creates an obsession to seek and find. Several years ago the mandevilla vine was one such obsession. Locating one was not that easy, but happily it is on its second winter inside brightening the gray days with hope of spring. Known for its showy flowers, the genus Mandevilla includes plants that were formerly called Dipladenia. There are about 100 species of this tropical woody vine. Most species overwinter only in the tropical South (USDA 9–11). In the Northwest they need to be brought indoors before the first freeze and treated as a houseplant during the winter months. In the spring, mandevilla can be returned outside after the last spring freeze or after the all threat of frost has passed. Mandevilla is best trellised in containers. Its pink trumpet shaped blooms create a show against its attractive shiny evergreen foliage. As a houseplant, mandevillas need curtain-filtered or bright indirect sunlight. Plant in a mixture of equal parts peat moss, potting mix and builders' sand. In spring and summer, feed every two weeks with a fertilizer high in phosphorus such as 10-20-10. Outdoors, mandevillas flower best in bright sunlight. Shade and cooler temperatures will slow their performance. They need rich, well-drained, sandy soil with humus added. Well drained soil is critical as these plants can be very sensitive to over watering. Allow plants to dry between waterings. Be sure to water slowly and thoroughly. Provide a frame, trellis or stake for support. Pinch young plants to induce bushiness. Plants should be moved indoors before any hint of frost. To be safe, generally, 45° F is the minimum temperature for mandevilla to thrive. Before bringing indoors, check carefully for pests. Remove any diseased or dead leaves by hand and douse with a forceful spray of water to dislodge the pests. Move the plants to a lighted location where the temperature is above 45° F to 50° F. Reduce the frequency of watering to coincide with the plant's dormant period induced by the cooler temperatures and shorter days. In late winter or early spring before growth begins, prune by removing old, crowded stems and shortening others. Mandevilla responds readily to harsh pruning and will return bushier and bloom the same summer on the new shoots. New plants can be propagated fairly easily from hardwood cuttings. Varieties Mandevilla x amabilis "Alice du Pont" is a woody, twining evergreen vine. It grows to a height of 20 feet but is much shorter when grown in a container. The leaves are dark green, glossy, oval and 3 to 8 inches long. Clusters of pure pink, flared, trumpet-shaped, 2- to 4- inch flowers appear among the leaves, spring through fall. Even very small plants in 4-inch pots will bloom. This cultivar grows well in hanging baskets. Pinch off tips of new stems to induce dense growth. Another cultivar is "Monte", commonly known as Summer Snow with sparkling white 3- to 4inch flowers against dark glossy foliage. Mandevilla "Laxa" or Chilean jasmine (although it is native to Argentina) is a climbing, woody, deciduous vine. It grows to 15 feet. Leaves are opposite, oblong or heart-shaped at the base. They are 2 to 6 inches long, thin and dark green with gray-green undersides. Clustered summer flowers are white, 2 inches across and trumpetshaped with a powerful gardenia-like fragrance. Provide rich soil. If the plant becomes badly tangled, cut it to the ground in winter. It will bloom on the new growth. Roots are hardy to about 5° F. Mandevilla splendens is an evergreen similar to "Alice du Pont", with the same bloom period. The leaves are narrow, pointed and 3 to 8 inches long. The trumpet-shaped flowers are 2 to 4 inches across, pale pink when they open, with rose-pink eyes. As the flowers age, their color deepens to rose. The stems of M. splendens reach 10 to 15 feet in length. Some red cultivars of this species are "Red Riding Hood" and "Scarlet Pimpernel". ,