How to Grow, Propagate, and Care for Dipladenia

Dipladenia is considered the perfect flowering plant because it is easy to maintain, blooms profusely, transplants easily in pots or the ground, and has a long life. This increasingly popular plant also has many new colors and varieties to choose from. You will find trumpet-shaped flowers in shades of pink, yellow, red, and white, punctuating glossy, dark green leaves. We spoke with a gardening expert for the best tips on growing, propagating, and caring for Dipladenia for beautiful blooms year after year.

Where to Grow Dipladenia

Dipladenia thrives in containers, as a hanging plant, or in the ground, but Myers suggests planting them in containers and then training them on a trellis, allowing the flowers to become the focal point.

"They can be the trailer, thriller, or filler," she explains, adding that they're commonly mixed in containers with other sun-loving plants. These flowers are also perfect for attracting pollinators, especially butterflies and hummingbirds.

Dipladenia Care Tips

Dipladenia needs the right environment and conditions to thrive—here's how to successfully care for them.

Temperature

These plants are native to the tropics and are considered hardy in zones 10 to 11. Because they don't tolerate temperatures below 45 degrees Fahrenheit, Myers suggests either growing them annually or moving them to a sunny spot indoors come the winter (another good reason to plant them in pots).

Pruning

In line with their low-maintenance reputation, Dipladenia shouldn't need much (if any) pruning. Myers says these plants don't require deadheading either, as the blooms fade and drop on their own. However, if the plant is trained on a trellis, some pruning may be necessary for the best possible growth.

How to Propagate Dipladenia

When propagating Dipladenia, it's important to first check the label to make sure your particular variety isn't patented. "It's illegal to propagate patented varieties," Myers explains. "This restriction allows breeders to recoup some of their money spent developing new varieties, and helps gardeners in that breeders can continue to introduce new plants that perform better in our gardens."

If you were hoping to propagate a patented iteration, it might instead be worth a visit to your local nursery to see if any new varieties have recently been added to their offerings.

Propagating Dipladenia From Cuttings

When propagating Dipladenia plants, Myers says that you have two options: The first is to take a 4- to 6-inch cutting from the green, pliable tip of the plant (avoid the older, wood-like section of the stem). Dip this in rooting hormone, and stick it in a moist, well-draining potting mix or vermiculite.

Propagating Dipladenia From a Layering Technique

The other option is to propagate with a layering technique, which allows the new plant to be fed all its nutrients by the parent plant while it starts. For this, leave the stem attached to the parent plant, but use a knife to cut halfway into it, creating a notch about 9 inches below the tip (you don't want to fully cut the stem, so you should wound it, or twist it until it cracks).

Treat the cut area with rooting hormone, and bury the notched area in the same soil or another pot just beside the original. To keep the notched and buried stem in place, you can set a stone right on top of the soil. Once the new plant is rooted, disconnect it from the parent plant, and voila! You have a new Dipladenia.

How to Transplant Dipladenia

Dipladenia can stay in the same pot for a long time. "These are very resilient plants," explains Myers. "You may not need to transplant them, as they're tolerant of being somewhat pot-bound." Annual transplanting, however, might help keep your Dipladenia looking its best. In this case, Myers recommends choosing a planter size just 2 inches larger in diameter. A pot that's too big will allow the soil to hold water longer, which can lead to root rot, she says. This kind of move can also temporarily stall blooming.

If you've purchased a small plant that's on a trellis and want to move it to a larger container, Myers says it's best to minimize the disturbance at the root collar (where the stem joins the roots). She typically gives the plant a good watering in the morning before transplanting later in the day, then another watering once the plant has been successfully moved. Tease apart any encircling roots to encourage them to expand into the surrounding soil in the larger container, she advises.

How to Fertilize Dipladenia

Many of the potted Dipladenia plants sold in stores have some fertilizer in the soil already, so you may not need to add more right away. Myers says to check the label for more information; if yours does include a slow-release fertilizer, hold off on feeding the plant for another month or so.

"I find that using a slow-release fertilizer like Milorganite once a year in the springtime is all I need," says Meyers. But take caution—too much nitrogen may interfere with flowering, so don't overdo it.

Pests and Diseases

While low-maintenance, Dipladenia may develop some diseases and attract pests and insects if left unattended. Aphids, mealybugs, spider mites, and scale can develop quickly if they're present. You may notice some black spots, fine cobwebs, and even eggs or larvae. To get rid of them, spray them with a solution of water and neem oil, antibacterial soap, or miticide.

Leaf spotting is common if your Dipladenia doesn't have proper air circulation or if it's situated in a poorly ventilated, high-humidity area. This is a fungal infection, so you may want to look for fungicide if you're constantly seeing bruised or ill-colored leaves in your plant.

Dipladenia vs. Mandevilla

Dipladenia and mandevilla are often confused. Dipladenia, a shrub, and mandevilla, a climbing vine, have similar trumpet-shaped blooms. However, Dipladenia does not require support to grow, and it produces smaller flowers.