My mandavilla is full sun, watered daily, and presently is hanging from a pergala and was growing vigorously. In fact, I have two and the one in question was the prettiest. It is now losing blooms, leaves are shrinking, and in general looking very sickly. It's campanion is still doing nicely. What is going on? I have never had this to happen. Both had reached the top of the structure and were growing so well.....thank you for your advice...before it's too late!

Hi Peggy,

Have you checked for insect pests? Common Mandevilla insect pests are mealybugs, scales, whiteflies, or red spider mites. Look closely under the leaves and between the leaf axils. You may use an insecticidal soap to treat the insect pests. If you cannot find any pests you may want to bring a sample into your local Extension office. http://www.ces.ncsu.edu/. Actually seeing the plant is very helpful in diagnosing problems.