Mandevilla , also known as rocktrumpet, is a genus of flowering vines that grow in tropical and subtropical climates. The five-petal flowers are often showy and fragrant, typically coming in shades of pink, red, and white. Plus, the flowers sometimes have yellow throats. They generally bloom in the summer and can stretch into fall, though in warm climates they can bloom year-round. Some species within the genus have smaller but more plentiful blooms while others have fewer but larger blooms. The foliage is usually a glossy green. Within their growing zones, mandevilla plants can be grown as perennials; gardeners outside of their zones often like to grow them as annuals, especially in container plantings. These fast-growing vines should be planted in the mid- to late spring once the temperature is reliably warm.
Mandevilla plants are fairly easy to care for as long as you get their growing conditions right. These vines thrive in lots of light, warmth and moisture. Plan to water whenever the soil begins to dry out, and feed your plant during the growing season.
If you wish to promote a bushier growth habit on these vines, pinch back the stems in the early spring. If you let them naturally grow as vines, it’s ideal to provide them with a trellis or other structure they can climb around. These vines also look great in hanging baskets.
These vines grow and flower best in full sun, meaning at least six hours of direct sunlight on most days. But they will tolerate some shade and might even appreciate shade from hot afternoon sun. A perk to growing them in containers is you’re able to move the plant out of harsh sun as needed, so the foliage doesn’t get scorched.
These flowers need sandy, well-draining soil with plenty of organic material mixed in. A good potting mix is a combination of peat moss, builder’s sand and leaf mold. A slightly acidic to neutral soil pH is best, though they also can tolerate slightly alkaline soil.
Unlike many flowering plants, mandevilla species can tolerate some dryness and continue to flower. That said, they prefer a consistent level of moisture, so aim to keep the soil damp but not soggy. Water slowly to give the soil time to soak up the moisture. And spray the leaves as well to knock off any pests and raise humidity around the plant.
Temperature & Humidity
These plants require warm temperatures and high humidity. Temperatures should be at least 60 degrees Fahrenheit during the day and 50 degrees Fahrenheit at night for mandevilla to be planted outside. If you live in a dry climate, regularly misting your plants will help to keep humidity levels up.
Fertilize in the spring with a slow-release, balanced fertilizer. Or use a liquid fertilizer at half strength every two weeks from spring to fall. It also can be helpful to mix some compost into the soil.
Is Mandevilla Toxic?
All parts of mandevilla plants are toxic to people and animals when ingested. And sap from the plants can cause skin irritation, as well as allergic reactions in those who are sensitive to mandevilla species.
Symptoms of Poisoning
Symptoms of poisoning via ingestion include upset stomach, nausea, vomiting, diarrhea, and sores around the mouth. And symptoms from skin contact with the sap include redness, pain, itching, and sores. Most cases are mild, but it’s still important to contact a medical professional if you suspect poisoning.
Potting and Repotting Mandevilla
When initially potting your mandevilla plant, choose a container that’s only slightly larger than its root ball. Make sure it has ample drainage holes. A container that’s too big can cause the plant to expend more energy on producing roots than growing flowers, so you might see fewer flowers until it has expanded its root system.
However, once you see roots creeping out of the container, it’s time to repot. Because these are fast-growing plants, you’ll likely need to repot annually in the spring. Select just one pot size up. Gently remove the root ball from the old container, set it in the new container, and fill around it with fresh potting mix. Then, water the soil.
Common Pests & Diseases
Mandevilla plants generally don’t have any serious problems with pests or diseases. However, they can attract spider mites, scales, whiteflies and aphids. You might notice tiny insects moving on your plants or see leaf damage and discoloration. If you have an infestation, apply an insecticidal soap as soon as possible.
Information courtesy of TheSpruce.com