Modern cotton production requires the use of growth regulator Mepiquat Chloride (MC) to configure crop for mechanized production. Proper timing and rate of applications of MC depends of plant growth status, environmental conditions and a complex interaction between these two factors. We developed and tested a model which uses periodic measurements of plant growth parameters to determine the time and rate of MC applications. The model has been named ‘Benchmark'. Plant measurements, which include height and main stem node number and plant population, are used in the model to estimate plant biomass. Plant biomass is used to determine the rate of MC application needed to maintain main stem elongation at desired rate, as defined by the user. Periodic changes in plant biomass accumulation are used in the model to determine the need of additional applications of MC. This presentation reports on the validation and uses of Benchmark to determine the rate and timing of Mepiquat chloride applications under research and commercial field conditions in the USA, Australia, Brazil and other countries.