Dipladenia Plant. An instructional video on how to prune back your dipladenia before you bring it inside for overwintering. The dipladenia plant (rocktrumpet) mandevilla relative, bushy downward hanging growth habit, evergreen, good for hanging baskets or on trellis. If you are a resident of cold areas, you can shift them inside during the fall. The dipladenia's hardy nature and handsome, brightly coloured flowers have made it a favourite pot plant in australian home gardens.