The quaternary chloride, Impact, applied singly and in combination with other quaternary plant growth regulator compounds has demonstrated several beneficial responses in cotton production. Applications of Impact during the period of pre-bloom to four weeks past first bloom have resulted in increased boll set and earlier maturity, generally resulting in increased yield. There is typically no direct effect on the vegetative growth or development of the treated cotton plants. Impact plus Pix application have resulted in consistent synergistic effects on cotton where excessive vegetative growth suppression is desired.