Limitations on available feed in dry areas affect the performance of livestock. Forage cactus is an excellent option in dry areas of the world; however, understanding water consumption in the forage cactus is essential for improving the management of water resources. The aim of this study was to measure the yield, daily and accumulated evapotranspiration (ETc), and crop coefficient (Kc, Kcb and Ke) in the following cactus species grown in a semi-arid environment over five crop cycles in three experiments: Orelha de Elefante Mexicana-OEM; Miuda-MIU; IPA Sert & acirc;nia-IPA; F8; Orelha de Elefante Africana- OEA and V19. The ETc, Kc, Kcb and Ke were determined per phenophase under conditions of maximum productivity. The plants of species Opuntia (OEM- 28.6 Mg ha-1 and OEA-19.4 Mg ha-1) have better agronomic performance in dry environments than plants of species Nopalea (V19- 11.5 Mg ha-1, MIU- 10.3 Mg ha-1 and F8- 7.8 Mg ha-1). The variation in ETc was most closely related to the duration of each phenophase and resulted in the following mean values: OEM- 2.74 mm day-1; OEA- 3.71 mm day-1; V19- 3.03 mm day-1; MIU- 2.71 mm day-1 and F8- 2.85 mm day-1. In species of Opuntia, Kcb is more important for Kc, whereas in species of Nopalea, Ke is the more important, with both accounting for up to 78% and 86% of the total ETc, respectively. The intrinsic characteristics of each species influence the growth dynamics of the crop and, consequently, the water requirement, highlighting the importance of adapting water management based on the type of clone.