Fertilizer Management for Citrus Orchards
The Law of the Minimum Nutrient" means that in citrus trees, as in other crops, the growth of the plant is limited by the nutrient element present in the smallest quantity, even if all other nutrients are present in adequate amounts. It is of the utmost importance in citrus production to know which, if any, nutrient element is the limiting factor. If there is a deficiency of any nutrient, then the fertilizer program must remedy this.
Any increase in fertilizer applications will give a yield increase. However, the yield increase is highest from the initial unit of fertilizer applied. As more fertilizer is added, the yield increase becomes smaller and smaller. This is known as "The Law of Diminishing Returns".
Hence, the amount of fertilizer which growers need to apply to get the maximum yield is not necessarily the same as the amount needed to get the maximum economic yield. It is the second, the maximum economic yield, which gives the best return for applied fertilizer. It is this yield level which growers should try to achieve.