How to grow amazing vine mandevilla from seed
Soil and Water
When planting outside, select a site with good drainage and rich soil. Amend the planting area with compost or other organic matter to support the blooms. Water regularly to keep the soil moist but not overly wet.
Temperature and Humidity
The preferred temperature range for mandevilla that grows outside is 68–90°F. Anything lower than 50°F is likely to damage the plant. If the plant is overwintering indoors, keep the temperature in the 60–65°F range at night and 70°F or warmer in daytime.
Like most vigorous plants that bloom for long periods, mandevilla benefits from a good dose of fertilizer every once in a while.
Pruning
If the plants get a little too wild for your liking, mandevilla can be pruned or trained to keep it in bounds. Plus, this will encourage more branching and blooms.
Potting and Repotting
When potting a mandevilla, use a lightweight, well-draining potting mix. Trim any dead or damaged roots, and position the plant at the same depth as in its previous container. Repot mandevilla every year or two in the spring in a pot only one size larger than the current container.
Pests and Problems
Mandevilla has no major pest problems, but it can attract mealybugs, aphids, and scale insects. The plant is usually ignored by deer and rabbits.
How to Propagate Mandevilla
You can propagate mandevilla from cuttings or seeds. In the spring, take 3-inch cuttings from the plant tip or side shoots and remove all but the top two leaves. Dip in rooting hormone and plant in a well-draining potting mix. When starting from seeds, use fresh seeds. Wait until they dry on the plant, then harvest the seeds, soak them in water overnight, and plant them in well-draining soil.
