Michael Dirr

Professor of Horticulture (retired)

Michael Dirr

Michael Dirr, professor of horticulture (retired), has introduced more than 100 new plant varieties to the horticultural world and, through his lifelong passion for plants, has inspired generations of students, gardeners, and professional horticulturists. Many of his introductions are licensed worldwide; others have contributed significantly to the nursery economy in Georgia and the U.S. Often called the Hydrangea Guru, he developed the varieties ‘Lady in Red’ and ‘Twist-n-Shout,’ the first of many patented releases with improved traits such as cold hardiness, repeat blooming and/or drought tolerance. Among Dirr’s other top-selling introductions are the abelias ‘Rose Creek’ and ‘Canyon Creek,’ the buddleias ‘Attraction’ and ‘Bicolor,’ the fothergilla ‘Mt. Airy,’ the ‘Dazzle’ line of crape myrtles, and his latest gardeniaHeaven Scent.’ Top tree introductions include a wide variety of maples, elms, ginkgos, ashes and magnolias. He has written more than 300 scientific and popular publications and is the author of 12 books, including Dirr’s Hardy Trees and Shrubs: An Illustrated Encyclopedia, and The Manual of Woody Landscape Plants: Their Identification, Ornamental Characteristics, Culture, Propagation, and Uses, the country’s most widely used teaching and horticultural reference text. This volume, which was honored by the American Horticultural Society as one of the greatest garden books of the past 75 years, has sold more than 500,000 copies.