Watermark KomplettprogrammThe use of Watermark Granular Matrix Sensors is specifically recommended for situations with longer time lags between water applications, i.e. in situations with higher fluctuation of soil moisture, for example in cases like irrigation by irrigation machines or in crops which need some degree of water stress or which are generally cultivated at the drier end. Besides the read-out equipment by Irrometer, Watermark Sensors also can be easily incorporated in complex data collection systems. For details please see chapters Now-SMS and iMetos.


Watermark Sensors measure soil water potential between 0 and 200 Centibar (0-200 kPa), are maintenance free and frost proof, and are buffered against varying salt content (EC value) in soil solution. Interpretation of data is easy, since measurement result is valid for all soil types. Watermark Sensors are durable and low cost, offer an accurate measurement result and have been field approved since decades.

Working Principle

Watermark Sensors consist of two electrodes, which are embedded in a special granular matrix. The sensors are protected by a stainless steel cover. Surrounding soil and the granular matrix inside a Watermark Sensor come to an equilibrium of soil water potential. The granular matrix has a varying resistance to electrical power (AC), depending on it's moisture content. This resistance is converted by the readout meter into soil water potential (unit Centibar).

Typical Applications

Irrigation scheduling in vegetables, asparagus and softfruit, irrigated by an irrigation machine, irrigation scheduling in vineyards, fruit trees, hops, potatoes, sugar beet, arable agriculture and seed production. Use in golf, garden and landscape irrigation.



You'll find videos and manuals about the installation of Watermark Sensors on our Homepage.

For tensiometer installation tools please see section accessories.