Dr. William Ackerman served until his retirement as a research horticulturist at the U.S. National Arboretum in Washington, D.C. He continues his research and experimentation with hybridization of cold-hardy spring- and fall-flowering camellias and the development of commercially acceptable yellow camellias. Many of the camellias that Dr. Ackerman has bred, known as Ackerman Hybrids, are available commercially. Dr. Ackerman is a former president of the Camellia Society of the Potomac Valley and has written or been the subject of more than 200 research papers, book chapters, and popular articles. He also wrote Growing Camellias in Cold Climates (2003).