Influencing Table Grape Color
Most consumers seek a large, evenly sized grape bunch of consistent appearance. Color is important, with green, red or black grapes favored over those of more intermediate colors. The correct crop nutrition will also affect table grape color.
Crop Nutrition and Table Grape Color
Potassium
Potassium plays the central role during transportation of photosynthetic products to support growth and development processes. It is common field practice to use potassium to improve table grape skin color. High potassium on the other side will reduce skin color, so balanced nutrition is important.
Iron
Foliar urea (low biuret) after fruit set, in low nitrogen regime can be used to improve table grape color. However, too much nitrogen can reduce color. This can be minimized by leaf pruning just after veraison.
