The beautiful Mandevilla is a tropical flowering vine. I am not familiar with the name Dipladenia. Mandevilla survive in mild winter areas only so if you live where winter gets below freezing you will need to bring your potted mandevilla indoors or into a greenhouse so it won't freeze. This heat loving plant will not bloom during cool weather and is susceptive to spider mites especially when grown indoors with low humidity.   You can prune back long tendrils to keep it bushy but does best with a trellis or other support to grow upward.  Use a slow release plant food such as Osmocote in the spring and water when top one inch of soil is dry. Water less in winter when you plant to go dormant. Grow against a west or south facing wall or on sunny patio as this vine loves heat. Keep growing, Marianne Binetti