Cuttings from redbud trees may prove difficult to root. According to Professor F.E. Larson from Washington State University's horticulture department, many cuttings may have to be taken during the summer months in order to get the small green stems to root properly. Age of the stock tree will also play an important function in the rooting process. Stock taken from older trees may have a more difficult time rooting than cuttings taken from seedlings.
Test the mother stock plant for viable cutting by attempting to break the greenest portion of the limb with your finger. If the end of the limb breaks easily, the mother plant maybe viable for taking cuttings from.
Cut the end of a green limb with the knife to a length between 6 inches and 8 inches. Take at least 5 cuttings from the tree, from separate limbs, for one 6-inch pot. Remove any lower leaves next to the cut end. The cutting should be bare approximately 3 inches to 4 inches from the cut.
Dip the cut ends of the redbud tree cuttings into the rooting hormone powder. Cover the lower portion of the cuttings up to 2 inches with the white powder.
Fill the 6-inch pot to within 1 inch from the top lip with the soil medium.
Insert the cuttings into the soil medium approximately 3 inches to 4 inches deep. Evenly distribute the five cuttings in the pot.
Mist the cuttings thoroughly with the spray bottle. Allow the water to drip from the cuttings into the soil mix.
Cut the bottom from the 2-liter soda bottle with the scissors. Keep the plastic cap in place on top of the bottle.
Place the soda bottle over the cuttings and into the plastic pot to create a mini greenhouse. The diameter of the soda bottle will fit just inside the 6-inch diameter pot. Water the cuttings when the interior of the soda bottle becomes dry.
Pull a single cutting from the growing medium in the pot after 12 weeks. There should be approximately 1 inch of root growth at the bottom of the new seedling. Transplant the rooted seedlings into separate pots.
Transplant the new seedlings to their permanent outdoor locations after two full seasons of growth in the separate pots. Plant during the redbud's dormant season, or when all leaves have fallen from the seedlings in late fall.