The cultivation of yellow pitahaya (Hylocereus megalanthus) is increasing in tropical regions due to its nutritional value and market potential. Yet, agronomic strategies integrating nutrient and hormonal regulation remain scarcely studied. This research evaluated the combined effect of potassium (K₂O) and gibberellic acid (GA₃) on yield and fruit quality in field-grown pitahaya in the Peruvian Amazon using a 4 × 2 factorial randomized block design with four potassium doses (0, 50, 100, 150 kg ha⁻¹) and two GA₃ levels (0 and 50 mg L⁻¹). The combination of 100 kg K₂O ha⁻¹ and 50 mg L⁻¹ GA₃ significantly improved fruit performance, with fruit weight (369.5 g), yield (12 t ha⁻¹), volume (322 cm³), and soluble solids (22.8°Brix), while acidity decreased (pH 4.87 vs. 4.55 in the control). Potassium alone had a limited impact on fruit weight per plant, but under GA�...