This paper reports the results of an experiment to quantify the fruiting characteristics of eight cotton varieties to enable crop simulation models to more accurately reflect yield and maturity of current varieties. Characteristics measured were time to first square, square period, and boll period, and their subsequent effects on crop maturity. Thennaltime to first square and bll period were correlated to the maturity ranking of the varieties. However, differences in the length of these periods compared with other reports indicates the need to pursue better methods to quantify these characteristics