Abstract In Opuntia ficus - indica (L.) Miller, the wide range of environmental conditions in which it grows implies a great variability in fruit yield and fruit ripening, among other issues. In this research work, we studied the dependence of fruit weight or number of fruits per cladode on fruiting cladode fresh or dry weight for the ‘Rojo Pelon’ variety by means of the boundary line approach and using 60 terminal fruiting 1-year-old cladodes and 480 fruits of O. ficus - indica variety ‘Rojo Pelon’ from twenty 6-year-old trees distributed at a density of 625 plants ha −1 . Fruiting occurred on cladodes with fresh and dry weights surpassing 144 g and 14.4 g, respectively. Cladodes with ≈144 g to ≈964 g of fresh weight produced 6 fruits or even more; cladodes with ≈30 g to ≈70 g of dry weight increase the probability of producing 11 fruits or more. The maximum fruit weight of ≈116 g may be related to ≈550 g of cladode fresh weight, and the maximum number of fruits of ≈15 could be strongly linked to ≈558 g of cladode fresh weight. The maximum fruit weight of ≈117 g may be considerably attributed to ≈61 g of cladode dry weight, whereas the maximum number of fruits of ≈15 can be strongly ascribable to ≈50 g of cladode dry weight.