Both dipladenia plants leaves are dried out-crispy.Are they able to be saved?

Question

We live in Montana near Helena. Will they, the plants, survive and come back after the winter? What should we do? Did we kill them? They were full of blooms when we brought them indoors, Then the leaves started dying on both plants

Answer 1

Cold temperatures can kill them, but it did not likely damage them so much that they cannot be saved. Bringing them indoors can shock them a bit too.

This article will help you to care for these indoors: https://www.gardeningknowhow.com/ornamental/vines/mandevilla/growing-a-dipladenia.htm