Flowering Tropicals that Beat the Heat
It gets almost tropically hot here in the Triad during summer. How do you keep your patio looking colorful in summer when plants are suffering in the heat and humidity? With plants that come from hot, humid climates of course! We'll focus on Mandevilla, Dipladenia, Lantana and Hibiscus, but most flowering tropicals have similar requirements for light, water and fertilizer.
Mandevilla, Dipladenia (closely related to Mandevilla), Lantana and Hibiscus have similar requirements:
Potting
Plant in a fairly large container for best results, using a potting or container mix, never garden soil. Make sure your container has drainage holes. If planted in the ground, amend the soil with soil conditioner. Here are some considerations for specific types of plant:
Mandevilla
They are strong vining plants reaching 10’ or more in height, so provide a trellis, sticks or strings for them to twine around.
Dipladenia
Some varieties are bushy, while some vine like their close cousin Mandevilla. The vining types usually have some tendrils growing up when you purchase them, or are on a trellis. The bushy types make great pot or hanging basket plants. Provide vining types with a trellis, sticks or string to climb.
Lantana & Hibiscus
If you have a tree form Lantana or Hibiscus, use a pot that is large enough & heavy enough to support it without blowing over in strong winds, or provide protection from wind.
Light
Most warm-season tropicals require at least 6 hours of full sun a day for good blooming. Hibiscus prefers some afternoon shade and will flower well with less full sun than Mandevilla or Dipladenia. Lantana loves sun, so give it as much as you can. If the location where you place your plants gets sun from only one side, turn them every few days to prevent leaning.
Water
Water when the top inch of soil is dry. Avoid letting the plant wilt as it can affect developing flower buds.
Fertilizer
Use a “bloom booster” fertilizer every other week according to label directions for loads of flowers all summer. Using a high nitrogen fertilizer will result in plenty of green growth, but fewer flowers (It can also attract aphids).
Pests
Watch leaves and stems for mealybugs, whitefly, aphids and spider mites. Treat with any pesticide labeled for ornamentals according to package directions if spotted.
Pruning
Usually not needed during summer, but feel free to shape plants as you see fit. Lantana trees sometimes grow so vigorously that the branches begin to droop from their own weight. In this case shortening the branches can prevent breakage. Lantana is very forgiving and sprouts again quickly after pruning.
Want to keep your tropicals through the winter? Here's how!