Giant potato creeper is strictly a tropical in New England, in the garden only by intent and at no little expense: Overwinter a specimen or buy a new plant each Spring. Tall verbena usually needs to be be planted only once, after which it seeds where it wants.
Both species crave heat and sun, and some spots—cracks between pavers that bake in Summer, in particular—seem foolproof habitat for verbena's seeds to overwnter and germinate. Figure out where the verbena is a sure thing, and then set your pot of potato creeper nearby. As vastly as these species' size and habits contrast, their flowers' colors and their preferred exposures match.