Poinsettia Height Control (1995)
Controlling height is critical in producing a high quality poinsettia crop. Breeding programs resulted in shorter cultivars, but managing height artificially is still critical to a salable crop. Traditionally, height control has been achieved with chemical growth retardants. Increasing concerns about chemicals have led to a renewed interest in nonchemical control. In greenhouse production, one nonchemical method that's economical and easy is daily temperature manipulation to limit stem elongation.
Source: • Georgia Commercial Flower Growers Association Newsletter