Potassium is important for the transfer of carbohydrates from the leaf to the fruit, improving pulp content and fruit size.
Splitting K applications into frequent and small doses provides the highest yield responses, particularly in high rainfall areas and on light soils.
Nitrogen in excess produces crops that are more at risk of disease, have smaller fingers, smaller bunches and reduced bunch conformity. Bunches can be poorly filled and more prone to dropping from the plant. They have a reduced green life after harvest.
Care has to be taken with the use of all sources of nitrogen to minimize leaching and 'little and often' applications are advisable. Nitrogen is commonly applied every two weeks in tropical plantations.
In trials, calcium nitrate increases root and sucker growth, and speeds leaf development, through raising soil and leaf Ca-supplies. This research also confirms reduced risk of root diseases and direct increases in leaf size from use of calcium nitrate.
This improved vegetative development as a result of using calcium has a direct effect on the number of hands/bunch, and finger length, increasing mean bunch weight.