The EC of the nutrient solution influences the growth and development of the plant. During the winter months a higher EC is used as this restricts the uptake of water. As a result, the cells in the plant do not elongate or “grow” as much. They remain smaller and have a thicker, stronger cell wall. The plant then appears darker, shorter and with smaller leaves.  In this situation, the plants put relatively more energy into the formation of flowers and fruit (a generative response).  If the EC is too low in poor light conditions (i.e. winter), the plant will produce too much leaf growth and too little fruit growth and hence will be too vegetative.

Conversely, a high EC under high light conditions (summer) will restrict water absorption too much and therefore the ability of the plant to cool itself via transpiration. Consequently, the crop will become stressed.

The EC also influences production and fruit quality. In general, a higher EC in the root zone environment leads to lower production and smaller fruit size. This is because the cells in the fruits take up less water, which results in a lower fresh weight. However, a higher EC results in better fruit taste. Therefore a compromise must be struck between fruit quality, yield and the vegetative and generative development for the crop.

It is important therefore to maintain the correct delta EC within the root zone environment (measured as the difference between the slab EC and drip EC). The value for delta EC differs for each crop type and time of year. For more details please refer to the crop specific water management guidelines for the Master™ slab by clicking here.