The use of plant growth regulators has been a common practice in the production of Australian cotton for at least two decades. The most common product has been Pix, which reduces plant height by stopping the production of the plant hormone (gibberellic acid) responsible for cell elongation. Many other plant growth regulators (PGRs) have been tested overseas, and some are commonly used in cotton production. A range of new PGRs (Glycinebetaine, GA3, PGR IV and AVG) where tested under Australian conditions. The use of Pix was also tested on a range of new cultivars to examine cultivar sensitivity.