Dipladenias (also called Mandevillas) are showy tropical vines desirable for their large, brightly-colored flowers. In warm climates, the vines are evergreen. There are more than 100 species of this vine, which are native to the tropics of South America, according to information published by Clemson University. Dipladenias make excellent container plants when trained to grow on a trellis, or dangling from a hanging basket, but they need tender care when the weather turns cool.
Place or plant your dipladenia where it will receive some bright light. In cooler climates, the plant thrives in full sun. In warmer climates, keep it out of direct afternoon sunlight, which can scorch the leaves of the plant. The gentle rays of the morning sun are beneficial, or all-day dappled shade works well for this plant. Indoor vines need curtain-filtered light, or indirect light such as a south-facing window, according to information published by Clemson University.
Apply a soil mixture that is composed of equal parts peat moss, loam and coarse sand. This will ensure that the soil drains well, which is an important requirement for this plant. Keep the soil consistently moist throughout the growing season (spring through summer). Let the surface dry down to a few inches during the winter.
Fertilize your dipladenia every other week during the growing season. A fertilizer high in phosphorous (10-20-10) works well for this vine, according to Clemson University.
Provide support for the vine in the form of a trellis or fence, if it is not in a basket. Pinch off newly-growing shoots in order to create a bushier shape.
Prune in early spring. Remove crowded, dead or broken canes. This plant will tolerate heavy pruning, so you can even chop it down to the ground and it will still sprout.