Prep plant growth regulator was applied at rates of 1.0 and 2.0 lbs a.i./A alone and in combination with Folex defoliant. The combinations with Folex were both at the same time as the Prep was applied and a week later. Significant increases in both defoliation and boll opening occurred. A maximum of 82% of the crop was picked at first harvest by the best treatments. There were no detrimental effects on fiber quality.