Big, beautiful mandevilla blooms open their trumpets to hummingbirds and other pollinators, making this flowering vine a summertime favorite.
Grow Mandevilla (Rocktrumpet) for Easy Summer Color
Updated on Oct. 23, 2024
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Mandevilla Care and Growing Tips
- Scientific name: Mandevilla spp.
- Common name: Rocktrumpet
- Zones: 9 to 11 or Annual
- Light needs: Full sun to part sun
- Water needs: Moderate
- Soil: Rich, well-drained
- Size: 1 to 20 feet tall and wide
- Attracts: Birds, bees and butterflies
This bloom-laden vine is a showstopper wherever it grows, and many summer gardens feature baskets or trellises full of its trailing flowers. The blossoms themselves spread several inches across, with a deep trumpet shape that hides nectar at its base. You’ll find this charmer available in red, pink, white, yellow, and more, all with glossy green foliage that’s attractive all on its own.
“Mandevilla blooms nonstop from spring to fall,” says Justin Hancock, horticulturist at Costa Farms. “Thanks to its subtropical nature, it holds up to heat and humidity better than a lot of traditional annuals, so you can count on it to continue putting on a show. It also has a good amount of drought tolerance and doesn’t require pruning or deadheading, making it a delightfully low-maintenance addition to the garden.”
Mandevilla (rocktrumpet) can be a hungry plant, and will benefit from regular applications of fertilizer, especially in nutrient-poor soils. Choose a fertilizer high in phosphorus to encourage blooms, and feed it every two weeks throughout the summer.
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Is Mandevilla an Annual or Perennial?
This subtropical species requires fairly warm temperatures year round and can’t tolerate frost. That means in most climates, people grow it as an annual. But in frost-free zones (9 and higher), you can treat this plant as a perennial, as long as you provide a little protection when night temperatures drop below 50 degrees.
Overwintering Mandevilla and Dipladenia
Some people bring rocktrumpet indoors to overwinter, but it can be a little finicky as a year-round houseplant.
Reader Darlene Collins wrote to Birds & Blooms and asked, “Do you have any tips for helping dipladenia (mandevilla) plants grow inside?”
“Back when I lived in Iowa, I had a mandevilla I brought in every winter,” Justin says. “I kept it in front of a west-facing window and it regularly produced flowers throughout the winter. Unless you have a really high-light spot inside, I wouldn’t recommend it as a year-round houseplant, but it’s easy enough to keep from year to year.”
Gardening expert Melinda Myers adds, “It is possible to overwinter dipladenias indoors for winter. Prune the plant back by about halfway to make it easier to fit your indoor growing space. Set it in a sunny window and use artificial lights if needed to boost the amount of light the plant receives.
The plant may drop leaves as it adapts from the outdoor growing conditions to the more challenging indoor environment. Water the soil thoroughly whenever the top few inches begin to dry. Pour off excess water or place a few pebbles in the saucer.
Make sure the pot sits on the pebbles above the water to prevent root rot. This extra humidity helps all indoor plants tolerate the dry air.
Do not fertilize yet. Prune the plant back and begin fertilizing in late February or early March to give it a good head start on the summer flowering season.
I have also had success overwintering these plants in a cool dark area in my basement. Cut the plant back to about 12 inches and water just enough to prevent the roots from desiccating. Move the plant to a warm sunny location in late winter and begin watering to encourage growth. Then start fertilizing when new growth appears and move it outside once the danger of frost has passed,” she says.
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When and Where to Plant Mandevilla
Plant mandevilla outdoors when daytime temperatures are in the 60s or higher, with nights in the 50s and up. Justin explains, “Mandevillas want all-day sun in a warm or hot spot, and well-draining soil. Fungal diseases can occur when it’s planted in wet, heavy soils. If you have heavy clay, you can usually avoid this pretty easily by planting in containers or raised mounds to help improve drainage.”
Justin also notes that while most people think of this plant as a vine, there are newer cultivars that have a mounding growth habitat instead, reaching only about 18 inches tall and wide. If you’d prefer to grow it in a border, look for the mounding types instead of vining types. Otherwise, provide something for it to climb on, or put it in a high-hanging pot to trail down.
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Do Hummingbirds Like Mandevilla?
Many people plant mandevilla specifically for the pollinators it attracts, like hummingbirds, butterflies and bees. In fact, it’s one of our top picks for vines that attract hummingbirds!
Mandevilla Pests and Diseases
In addition to being subject to fungal disease when grown in wet, heavy soils, this blooming vine can occasionally be bothered by spider mites, though Justin says they’re usually not a major issue. If you do encounter them, he suggests some solutions. “Spraying the plant’s foliage with water every day for a couple of weeks is a natural way to help combat spider mites; you can also use an insecticidal soap or miticide,” Justin says.
In some areas, oleander moth caterpillars can cause serious defoliation. But in general, this beloved plant is relatively pest-free in most gardens. And even better, it’s deer and rabbit resistant. (Note that this plant exudes a toxic sap, so wear gloves when handling and keep it away from kids and pets.)
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New Mandevilla Varieties to Grow
The Sun Parasol series is especially popular with gardeners, with flowers available in pink, red, white, yellow, and a lovely new delicate apricot shade that’s sure to be a hit. Justin also recommends keeping an eye out for Sun Parasol Bluephoria, a purple-blooming variety that’s hitting the market in limited numbers in 2024.
Next, learn how to grow trumpet honeysuckle for hummingbirds.
About the Experts
Justin Hancock is a horticulturist with Costa Farms, one of the world’s largest plant growers, known for houseplants and outdoor tropical flowers. Justin previously worked at Monrovia Plants and served on the board of directors for All-America Selections. He has a bachelor’s degree in horticultural science.
Melinda Myers is the official gardening expert for Birds & Blooms. She is a TV/radio host, author and columnist who has written more than 20 gardening books. Melinda earned a master’s degree in horticulture from the University of Wisconsin-Madison.
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