Produce buyers constantly prefer redder fruit. Some varieties develop redder colour than others. Although the red colour differs for each variety, it can be maximized in any of them by managing light intensities (shading, pruning) and nutrition.
Crop Nutrition and Stone Fruit Coloration
Phosphorus and Calcium
Phosphorus and calcium sprays have a direct effect on fruit coloration, increasing the levels of anthocyanins in the skin, and thus improving crop marketability. Phosphorus sprays applied to the fruit two to three weeks prior to harvest are particularly effective in improving coloration of peaches, apricots and plums.
Potassium and Nitrogen
Also potassium has been found to improve the red color formation on the skin of peach fruits.
Overuse of nitrogen can reduce fruit colour, leading to lighter color, peaches and nectarines.