Growth Response of Crapemyrtle to Geographical Area and Production Light Level

Abstract

Abstract The effects of geographic location and production light level on vegetative growth and flowering were evaluated as a means of accelerating the development of tree-form crapemyrtles. By the end of the first year of the experiment, Dynamite™, ‘Muskogee’, ‘Natchez’, and ‘Tuscarora’ grown in Oregon were as much as 42, 51, 43, and 92% taller, respectively, than plants in Alabama, while plants generally had less trunk diameter in Oregon. ‘Muskogee’ and ‘Natchez’ in both locations and ‘Tuscarora’ in Alabama were generally taller when grown under 50% shade than plants in full sun, while height of Dynamite™ was not affected by production light level. Trunk diameter of ‘Natchez’ in both locations and of Dynamite™ in Alabama was less when plants were grown under shade, while trunk diameter of ‘Muskogee’ and ‘Tuscarora’ was not affected by production light level. Flowering of plants grown under shade in Alabama was delayed, while no plants in Oregon flowered the first year. In the second year of the experiment when all plants were grown in full sun, all cultivars continued to be taller in Oregon, while trunk diameter remained greater in Alabama. The height advantage gained from growing plants under shade the previous year was not evident in any cultivar by the end of the second year, while trunk diameter was similar for all cultivars previously grown in full sun and under 50% shade. There was no difference in flowering of plants in Alabama previously grown under 50% shade and in full sun, while 50 to 100% of the four cultivars in Oregon flowered with no obvious difference due to prior production light level.