Insufficient or excessive irrigation can result in reduced yields, reduced specific gravity and increased incidence of tuber defects such as second growth, hollow heart and soft rot. Excessive irrigation will also increase production costs through leaching of fertilizers and higher pumping costs. Correct irrigation scheduling should minimize these problems. Tensiometers are simple and reliable tools that potato growers can use to schedule irrigations and maintain optimum soil moisture levels. The tube is filled with water and sealed with a cap.
Some tensiometers have an attached Bourdon vacuum gauge.
Others come with an electronic vacuum gauge that can be transferred from one tensiometer to another. Image Figure 1. As plants use water and the soil dries out, water is drawn out of the tensiometer through the ceramic cup. Because the tube is sealed, a vacuum is created and is measured on the gauge. Preparation and installation To give reliable readings, tensiometers must be prepared and installed correctly.