How to increase sugar yield

The final aim is to achieve high sugar yields and there are a large number of agronomic factors that can influence this.

Many of which are within the farmers control, given the specific growing systems and climatic/soil conditions. The right crop nutrition will also help to achieve the optimal sugar yield.

Crop nutrition and Sugar Yield


Correct N nutrition not only increases cane yield, but also improves the sucrose content in the harvested cane. However, excessive nitrogen use can reduce sugar quality, leading to lower sucrose contents. Moreover, it is important to balance nitrogen use with potassium to maximize sugar conversion, content and juice quality.


Phosphorus has a direct effect on sugar yield, not only through increasing physical yield, but also by increasing sucrose content in the harvested cane. It can also result in poor clarity in cane juice.


Potassium has a key role to play in sugar synthesis and its translocation to the cane. It also improves sugar quality increasing Pol and Brix levels and reducing fiber content. An adequate potassium supply also ensures a higher sugar yield. Luxury uptake though, adversely affects sugar crystallization.


Sugar is also influenced by magnesium supply and sucrose content is reduced where Mg nutrition is inadequate


Sulfur must be applied if sugar yields are to be maintained in the sugarcane crop. Research confirms that sulfur has an effect on a range of characteristics that influence sugar quality, including Brix, Pol, juice purity and CCS.


Boron has a direct effect on new root and shoot development. Some of the strongest effects from boron have been seen from applications to the furrow alongside the plant crop where the element improved early shoot growth and tillering leading to higher sugar yields.


Of all the micronutrients, zinc provides the largest response in the greatest number of trials. Peak demand of zinc is during establishment and tillering, hence the strong responses seen to zinc applied impregnated on the set or directly applied to the furrow. However, high yield responses also come from foliar zinc applied to the leaf on each subsequent ratoon crop. This is largely due to its effect on early root and shoot growth and the subsequent increase in tiller numbers leading to significant yield increases in the plant and following ratoon crops. Best effects are seen where zinc is applied alongside boron.