Cuttings from a climbing rose bush produce an exact duplicate of the original plant. Heirloom varieties of roses have no patent, which means you can take as many cuttings as you wish to generate more roses. While the old method of rooting a rose cutting under a glass jar works, an even more reliable way to get cuttings from a climbing rose bush to root is through the use of a rooting compound and a mini-greenhouse.
Gather cuttings in the early spring before blooming begins, or in the fall after the climbing rose bush has stopped blooming. Choose healthy rose bushes from which to acquire the cuttings.
Choose the ends of stems which have spent blooms or rose hips still remaining. These are the stems which will root most readily. Cut six- to eight-inch sections from the ends of the stems, at a 45-degree angle.
Remove the bottom leaves from the rose stem cuttings. Keep the upper two or three leaves intact to allow for photosynthesis.
Wet the potting soil and squeeze out any excess water, to make the soil feel like a damp sponge. Fill the growing pot with the soil and create deep holes in the soil for the climbing rose bush cuttings.
Pour a tablespoon of the rooting compound into a sandwich baggie. Dip the bottom two to three inches of the rose stem cutting into the rooting compound and shake off any excess powder. Place the cuttings into the pre-formed holes and tamp down the soil.
Place the growing pot into the clear plastic bag. Create a hoop from the wire of the coat hanger to go from one side of the growing pot to the other but over the cuttings. Pull the plastic bag up over the hanger and seal the top with a twist tie or rubber band.
Place the cuttings in a warm, bright location away from direct sunlight. Monitor the cuttings, keeping the soil moist and removing any dead or molded cuttings. After five to six weeks, the cuttings start developing a root system and may be transplanted to larger pots until the weather permits the new climbing rose bushes to be planted outside.