Two on-farm tests were conducted to evaluate the individual and combined effects of Pix and Prep + Def treatments on plant development, harvest dates, yields and fiber quality. Pix treatments did enhance earliness but reduced yields in the test where an early maturing, determinate variety was used. At the other location where a later maturing cotton was grown, Pix had less apparent effect on earliness but did increase yields slightly. In one test, Pix treatments also resulted in improved grades and higher returns per acre. The Prep + Def treatments resulted in slight yield decreases at both locations. The harvest-aid treatments did prepare the crops for earlier harvest but this advantage was negated by weather factors that delayed harvest about 3-weeks. Even with the delayed harvest, some improvements in grades were noted as a result of the harvest-aid chemical treatments.