Pitaya is a fruit that is becoming promising for cultivation around the world due to the quality of its fruits in terms of taste and their peculiar external shape. Because it is a recenttly cultivated crop, information about fertilization is essential to enable its production. In this sense, this study was performed aiming to evaluate different doses of K 2 O for pitaya cultivation. Hylocereus undatus and Hylocereus polyrhizus were studied under field conditions. Pitayas were cultivated at a 3 × 3m spacing, and four doses of K 2 O were tested: 0, 50, 100, and 200 g plant-1 , with a 2 × 4 factorial arrangement distributed in a randomized block design. The production per plant (kg and number of fruits) was evaluated in the