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The development of three cotton varieties was evaluated through the growth analysis technique. Study varieties were two of normal leaf (Clan Precoz and NuCotton 35B) and the other of okra leaf (Fiber Max 832). Vegetative and reproductive samplings effected at different days after planting (dap) allowed us to determine the (1) growth dynamics, (2) production efficiency and (3) the biomass distribution of the three cotton varieties. Seeding was conducted following the production system of narrow rows (0.76m, between rows; 0.20m between plants) to obtain a plant density of 65500 plants/ha. Varieties were distributed in a random block experimental design with six replicates. At four different dates (69, 82, 105 and 120 dap) two plants per plot were obtained to get the data of leaf area, total dry weight and dry weight of both vegetative and reproductive organs. Growth indexes such as crop growth rate (CGR), net assimilation rate (NAR), leaf area index (LAI), leaf area ratio (LAR), specific leaf area (SLA), leaf weight ratio (LWR) were estimated with the data obtained. Results showed that the study varieties statistically differed in the production rate and the indicators of the magnitude of the photosynthetic apparatus (LAR and SLA). Samplings also differed in biomass distribution.