Shrub · Apocynaceae
Dipladenia
Mandevilla sanderi
Provide full sun, warmth, and sharp drainage, and dipladenia produces trumpet flowers from early summer through fall.
Full sun
Every 3–7 days
45–84°F · 7–29°C
USDA 9–11
Overview
Dipladenia represents the bushy, mounding form of Mandevilla sanderi, a tropical vine native to Brazil and grown for glossy foliage and a continuous show of trumpet-shaped flowers. The plant sits in the dogbane family alongside oleander and periwinkle, and in common with those relatives every stem holds a milky sap. It earns its place as a patio and container subject that keeps flowering once the weather turns warm.
The naming comes down to commerce and growth habit. Specimens sold under the Dipladenia label keep a compact, bushy form with a trailing tendency that fits pots, baskets, and window boxes, while those labeled Mandevilla climb more strongly and reach a larger size. Cold-hardy only in zones 9 to 11, it stays outdoors all year in the mildest gardens and is grown as a summer annual or overwintered indoors everywhere else.
Sun suits it and saturated soil ruins it. Supply heat, light, and a fast-draining medium, and the flowering carries on through fall. Let the roots stand in waterlogged soil or expose the plant to a cold spell, and the bloom gives way to yellow leaves and dropped buds.
Care
The short version: full sun and warmth, a fast-draining medium that keeps the roots from sitting wet, a high-phosphorus bloom feed across the growing season, and gloves on every time you cut the sappy stems.
Light
Dipladenia sets the most flowers in full sun, and the stronger the direct light, the more buds it forms. It persists in partial shade or bright indirect light indoors, but in weak light the flowering thins out quickly.
Water
Hold the soil moist but never soggy during summer, allowing the top of the pot to dry between waterings. The plant resents wet feet and rots at the roots when left waterlogged, so cut back sharply in winter as growth slows.
Soil
Grow it in rich, sharp-draining soil, whether a sandy blend with humus or a peat-based mix. It tolerates a wide acidity range and does well across pH 6.0 to 8.0, but quick drainage counts for far more than hitting an exact figure.
Temperature
It does well between 45°F and 84°F (7°C to 29°C) and needs consistent warmth to keep flowering. Nights under about 50°F (10°C) bring it to a halt, and frost is fatal, so move it indoors ahead of the cold.
Humidity
Dipladenia prefers high humidity, and dry air shows its toll when spider mites move in indoors. Cluster it among other plants or place it on a pebble tray over winter to keep the surrounding air moist.
Feeding
Across spring and summer, apply a high-phosphorus bloom fertilizer such as a 10-20-10 every two weeks. The added phosphorus drives flowering instead of leafy growth, which is precisely what this plant should be doing.
Pruning
Pinch out the tips of new shoots to hold it bushy and compact, and trim lightly to shape the plant and take off finished blooms. Wear gloves for this work, because the cut stems ooze an irritating milky sap.
Repotting
Step it up a pot size every 1 to 2 years in spring. Roots circling out through the drainage holes, water passing straight through, or growth and flowering that have tailed off are all signals that the time has come.
Size & spacing
12–59 in (30–150 cm) tall
When to plant
Dipladenia thrives on warmth and has no defense against frost. Keep it indoors or sheltered until the cold genuinely lifts and nights hold above about 50°F (10°C), then plant it out for the season, and it blooms from early summer through fall.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: After all danger of frost has passed and nights stay above about 50 degrees F
- Harvest: Early summer through fall
Hardiness
USDA hardiness zones: 9–11
Temperature: down to -7°C
Troubleshooting
The leaves are where most dipladenia problems surface, driven either by sap-feeding pests or by roots held too wet. Spot the early signs and the remedy stays straightforward. Find the match below, then act before the problem spreads.
Stippled, pale leaves laced with fine webbing
Those symptoms point to spider mites, a pest that builds up fast in the warm, dry conditions a plant meets after it comes indoors for the cold months. Flip a leaf and check the underside for moving specks and faint webbing, or tap the foliage over a sheet of white paper to dislodge them. Hose the leaves down hard, apply insecticidal soap or horticultural oil, and lift the humidity, since the mites struggle once the air around the plant stops being dry.
Fix:
- Rinse foliage with a strong spray of water
- Treat with insecticidal soap or horticultural oil, repeating per label
- Raise humidity around the plant
Sticky stems with cottony tufts and small bumps at the joints
That signature belongs to mealybugs or scale, and whitefly or aphids may show up alongside them. Look closely at the leaf joints and stems for the white fuzzy bodies, the hard fixed bumps that mark scale, or a haze of whiteflies that rises when the plant is brushed. Touch small clusters with a swab dipped in alcohol, follow with insecticidal soap or oil, and separate the plant from the rest so the infestation has nowhere to travel.
Fix:
- Wipe off light infestations with an alcohol-dipped cotton swab
- Apply insecticidal soap or horticultural oil and repeat as needed
- Isolate affected plants to prevent spread
Leaves yellow and wilt while buds drop unopened
The usual culprit here is root rot brought on by waterlogged soil, though a cold draft can shock the plant into the same response. Tip it from its pot and inspect the roots by hand: sound roots stay firm and pale, while rotted ones go brown and soft. Allow the surface of the soil to dry before watering again, correct the drainage, and hold the plant somewhere warm above about 50°F (10°C) and away from cold drafts.
Fix:
- Let the top of the soil dry before watering again
- Improve drainage and ensure pots have drainage holes
- Move the plant to a warm spot above about 50 degrees F away from cold drafts
Tan to brown leaf spots that yellow before the leaf falls
This is anthracnose, a fungal disease that gets a foothold whenever foliage stays damp for long stretches. Look for tan to brown lesions that enlarge, yellow the leaf, and end in leaf drop. Strip off the spotted leaves and discard them, keep moisture off the foliage, and turn to a labeled fungicide only when the disease returns despite those steps.
Fix:
- Remove and dispose of affected leaves
- Avoid overhead watering and keep foliage dry
- Apply a labeled fungicide if the problem persists
Toxicity
Handle this plant with some caution. Every part contains a milky latex sap that can irritate skin and eyes and cause stomach upset when chewed, and no part of the plant is safe to eat. Put gloves on to prune, and keep the foliage beyond the reach of pets, livestock, and small children.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Mild
If a cat gnaws the leaves, look for drooling and stomach upset, occasionally with vomiting. These effects stay mild and generally resolve without treatment.
Dogs Mild
A dog that mouths the foliage may drool a little and feel queasy, with vomiting now and then. The reaction tends to clear quickly.
Horses Caution
The bitter milky sap deters most horses, yet a mouthful can still irritate the mouth and digestive tract. As a precaution, keep the plant clear of the paddock.
Rabbits Caution
A rabbit should never browse on this. The irritant latex can sting the mouth and disturb the gut, so keep it off the menu completely.
Livestock Caution
Goats, sheep, and cattle seldom go after it, but the sap can still irritate the mouth and digestion if they take a bite. Fence it off from grazing animals.
Birds Caution
There is no reason to let a pet bird near the leaves or sap, and the irritant latex could distress a small bird in short order. Keep it well beyond reach.
People Caution
None of this plant is edible. The milky sap can redden and irritate skin and sting the eyes, so put on gloves to prune and stop curious children from chewing it.
Wear gloves when pruning, as cut stems release a milky latex sap that can irritate skin and eyes; wash hands afterward and keep sap away from the face.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
Nearly all dipladenia on the market traces back to a handful of breeding series, each selected for compact, free-flowering plants that work in pots and baskets. These are the names you are most likely to encounter.
'Rio' series
A compact, bushy Dipladenia line bred to flower freely in containers and baskets, offering blooms in red, pink, and white.
'Sundaville' (Sun Parasol)
A series ranging from mounding to trailing that holds glossy foliage and trumpet flowers across the summer, including compact selections suited to hanging baskets and window boxes.
'Madinia' series
A bushy, well-branched Dipladenia line marketed for patios and pots, valued for its large flowers set against dark glossy leaves.
How to propagate
An existing dipladenia can give you new plants, either by rooting a cutting or by layering a stem that stays joined to the parent. Each method calls for patience, and each releases the same irritating sap, so keep gloves within reach.
Stem cuttingsModerate
Spring to summer · 4 to 8 weeks to root
During spring or summer, cut tips from shoots that are not in flower, and put gloves on first because the severed stems ooze an irritating milky sap. Set them into a moist, free-draining medium with warmth and bright indirect light, and they develop roots over the following 4 to 8 weeks.
LayeringModerate
Spring to summer · Several weeks to months
Through spring or summer, bend a low, supple stem down to moist soil and anchor it so it can root in place, a process that runs from several weeks to a few months. After the fresh roots take hold, sever the rooted portion from the parent plant.
Myths
A Dipladenia is not the same plant as a Mandevilla.
Both sit in one genus, and the word Dipladenia is simply an older trade label applied to the bushier forms of Mandevilla sanderi. What separates them is growth habit: Dipladenia keeps a bushy, mounding shape, whereas the types marketed as Mandevilla climb vigorously and reach a larger size. Botanically they are one and the same, and the genus Mandevilla takes in everything once called Dipladenia.