Mandevilla vine is not growing
I have a mandevilla that managed to survive our nasty winter of last year, but it is July now and the vine is only about 5 inches high and refuses to grow any bigger. The leaves are green and healthy with no signs of disease or pests. I've watered and fertilized with no results. It's planted in the ground, not a pot. We added compost to the soil we brought in for our raised bed. Any ideas as to why it's not growing?