Tips on Caring for the Mandevilla Vine

Planting Site

• Mandevillas grow well in pots in colder climates, or as an outdoor plant in tropical and subtropical climates. Choose outdoor sites that provide partial shade to prevent sun scorch on the leaves. Indoor plants perform better in a sunny location since they receive less light than outdoor plants. Mandevillas need rich but well-drained soil whether you grow indoors or out. Amend outdoor beds with compost before you plant, or use a peat-rich potting soil for potted mandevillas. Both plants require support for the vines. A trellis or fence works well outdoors, and a plant stake or pot espalier works well indoors.

Water and Fertilizer

• Water mandevillas as needed so the soil is moist but not waterlogged or soggy. Potted plants typically require watering every five to seven days, or when the top of the soil begins to dry out. Outdoor plants require approximately 1 inch of water per week from irrigation or rainfall. Both potted and garden vines need some fertilization to grow and flower their best. Fertilize indoor vines every two weeks in the spring and summer with a phosphorus-rich fertilizer, such as a 10-20-10 soluble houseplant blend. Feed garden plants in the spring with a slow-release phosphorus fertilizer.

Winter Care

• Since mandevillas don't tolerate temperatures below 45 degrees Fahrenheit, outdoor-planted vines must be moved indoors before winter cold. Keep them in a cool 55- to 60-degree-Fahrenheit location where they receive some sunlight during the winter months. Provide them with enough water so the soil doesn't dry out completely. Mulch around outdoor plants in the winter with a 2- to 4-inch-deep layer of leaves or straw. The mulch insulates the roots in the event of a cold snap in an otherwise warm climate.

Pruning

• Trim your mandevilla vine before new growth begins in the spring. Cut out any dead or damaged branches. Cut back overgrown or crossed wood to maintain the size and shape of your vine. You can also cut back outdoor vines to the ground if they are badly overgrown or damaged. The plant sends up new growth quickly and blooms the same year after severe pruning. Move potted plants to a sunny, warm area after pruning, and gradually increase watering as the plant wakes up from winter dormancy.