Cut a 4- to 6-inch cutting from the end of a Mandevilla vine. Choose a section with at least four or five leaf nodes.
Remove the leaves from the bottom half of the cutting. Treat the end with a powdered rooting hormone.
Fill a large pot with a mixture of potting soil and sphagnum moss. Mandevilla vines grow best in soil that drains well.
Plant the cutting in the large pot. Bury the end 1 to 2 inches below the surface of the soil. Tamp the soil down gently by hand.
Water the Mandevilla cutting so that the soil is damp but not completely saturated.
Place the container in a large, clear plastic bag. Tie the bag closed with a rubber band.
Situate the container in an area that gets strong, indirect sunlight. Direct sunlight is magnified through the plastic and can burn the vines.
Check the soil daily. Water the cutting when the soil is completely dry. Keep the plant moist but not completely soaked.
Check for root growth after two months. Continue to check once a week if roots haven't begun to appear. Once roots are over 2 inches long, remove the plastic bag.
Move the Mandevilla to an area with partial shade. Fertilize once a month with 10-20-10 fertilizer. Discontinue fertilizing during the winter months.