Location: Floral and Nursery Plants Research Unit
Title: Propagating Oakleaf Hydrangeas Authors
Submitted to: American Nurseryman
Publication Type: Trade Journal
Publication Acceptance Date: December 29, 2010
Publication Date: January 1, 2011
Citation: Reed, S.M., Overbey, S.L. 2011. Propagating Oakleaf Hydrangeas. American Nurseryman. 211:16-19. Technical Abstract: An oakleaf hydrangea breeding program at the U.S. National Arboretum’s worksite in McMinnville, Tenn. was started in 1996 for the purpose of developing attractive, compact oakleaf hydrangea cultivars suitable for use in small residential gardens. ‘Ruby Slippers’ and ‘Munchkin’ oakleaf hydrangeas were developed from this program and released in 2010. ‘Ruby Slippers’ grew to 3.5 feet high and 5 feet wide in 7 years. In early summer, it produces 9 inch long inflorescences that are held upright above the foliage. ‘Ruby Slippers’ flowers open white, but quickly turn pale pink and then deepen to deep rose color. ‘Munchkin’ is a bit smaller, reaching 3 feet tall and 4.5 feet wide after 9 years. It produces abundant, 6.5 inch long inflorescences that are also held upright above the foliage. ‘Munchkin’ flowers open white and gradually turn medium pink. Seeds obtained from pollinations were sown in shallow seed trays and germinated in a greenhouse. They were ready for transplant to the field or 3-gallon containers 5 months after being sown. Seedlings selected for superior characteristics were rooted from semi-hardwood cuttings that were propagated in a fog-filled greenhouse. Rooting occurred in 4 to 6 weeks and rooted cuttings were overwintered in a cool greenhouse. The following spring they were ready for transplant to 3-gallon containers.