Ramirez et al. (2012) published a review paper about mango flowering physiology. Mango flowering is a complex process. Low temperatures are important for mango floral induction under subtropical conditions. But also tip pruning and the use of potassium nitrate are effective methodologies to induce mango flowering, especially in Colombia. Different research papers prove the effectiveness of foliar application of potassium nitrate. Potassium nitrate was more effective in stimulating of vigorous flowering in mature shoots than in younger ones. Additionally, an increase in the number of panicles was observed. The beneficial effect of potassium nitrate sprays on flowering induction seems to be mediated by its dormancy-breaking property. It is especially used to induce off-season flowering. Potassium nitrate has been used to enhance flowering but also to increase the mango fruit retention (Oosthuyse, 1996).
Ramírez, F. and T.L. Davenport. 2010. Review: Mango (Mangifera indica L.) flowering physiology. Scientia Horticulturae, 126(2): 65-72.