Mandavilla is a truly lovely vine that can grow up to 15 ft long in full sun to part sun and if allowed to grab onto a pole or trellis will vine upwards. If no support is available the vines will grow outwards and then drop due to the weight of the branch, then upwards through itself (as seen in the picture below).
In a hanging planter daily watering during the warm summer temperatures is required with weekly fertilization. If planted in a ground bed maintaining proper moisture is still required but much less critical. Proper air movement around the plant will avoid leaf diseases such as mildew. Watch for aphids in the growing tips of the vines and spray accordingly.