The Impact of Water Quality on Crop Protection

One of our clients once said that farmers don’t really farm with cultivars. Instead, he believes that farmers, farm with soil and water and without these two elements, cultivating crops commercially would be impossible. Ultimately, how well a farmer looks after the soil and water will reflect in their crops. Producers that know how important soil and water quality are, are constantly testing and managing these natural resources to improve crop quantity and quality because water is not only a necessity for growth.


Producers use water as a delivery system for the equal distribution of biostimulants and agri-chemicals. If the water used during crop management is of poor quality, it will impact the effectiveness of the biostimulants and agri-chemicals used, the quantity and quality of the crops and the bottom-line of the farmer.


Farmers should know the quality of their water so that the necessary precautions can be taken to protect sensitive agri-chemicals. A full water analysis is by far the best option, but sometimes a quick EC (electrical conductivity) or pH measurement can supply valuable information. Despite these tests, there are certain aspects of water that cannot be measured by pH or EC and a full water analysis may be required in these cases.


Let’s take a closer look at the factors that influence water quality, the effects it can have on crops and how Remitto can help you.


  • pH Balance

 The alkaline or acidity levels of the base water and the agri-chemicals used can greatly impact the effectiveness of products. pH is an indication of how acidic or how alkaline water is. pH is measured on a scale from 0 to 14 where values lower than 7 indicate an acidic environment and values higher than 7 indicate an alkaline environment. The majority of water sources in South Africa have a pH ranging from 6.5 to 9 and therefore tends to be more on the alkaline side. The more alkaline the water, the more the pesticide will be antagonised by alkaline hydrolysis. This is the process where pesticides (especially certain insecticides) are degraded in alkaline water.



A simple pH measurement will indicate alkalinity, and the necessary steps can be taken to adjust the spray solution with buffer products. The choice of adjuvant is crucial for effective control. Each agri-chemical has specific requirements and only the correct adjuvant choice will satisfy those requirements and result in optimised control. Adjuvant choice makes an immense difference. Choose adjuvants very wisely to optimise and stabilise agri-chemicals under various conditions.


  • Salinity

 Electrical Conductivity (EC) is an indication of the salt saturation level of water. Dissolved ions in water contribute to EC and a high measurement will indicate a high salt content and potentially antagonistic water. If the EC is high, we can assume that at least one of the major antagonistic cations (calcium, magnesium, sodium and potassium) occurs in high levels. When the water used during application contains high levels of cations, the agri-chemical tend to bind to these salts and lower their effectiveness. Products that contain glyphosate,