The IRROMETER Company has been in business since 1951, manufacturing soil moisture measuring, controlling, and sampling instruments used worldwide for scheduling irrigation. Principal brand names are IRROMETER (Tensiometer) and WATERMARK (electrical resistance granular matrix sensor).

These soil water potential/tension measuring instruments originated in the early part of the 20th Century, and were used by soil and plant scientists to measure soil water status in their experiments. The IRROMETER Company was the first to produce commercially viable versions of this technology, and although this technology is scientific instrumentation, the instruments are inexpensive and easy to use for all irrigation applications. The use of soil moisture based irrigation scheduling has been proven an efficient way to deliver irrigation water for agriculture, nursery/greenhouse and landscape/urban irrigation. Further, the instrumentation can be used for controlling (automatic irrigation systems) and signaling (for data logging systems and inputs to weather stations).

We have been helping growers and researchers measure soil moisture since 1951, and offer two proven, effective, and well researched methods for measuring soil moisture.

The original “IRROMETER” instrument was the first commercially viable Tensiometer available, and is still the standard by which other methods are tested. Our instruments provide a direct measurement of soil water tension, which is the tension all root systems must overcome to extract water from the surrounding soil. Simple, reliable, and accurate, they are still the choice of many successful growers and consultants.

Our next option for soil moisture measurement is the WATERMARK sensor. This Granular Matrix Sensor (GMS) offers low cost, accurate readings, and easy integration with electronic reading equipment. First introduced in 1979, the WATERMARK sensor has grown in popularity and gained acceptance worldwide for reliability and accuracy in measuring soil moisture. For over two decades, the WATERMARK sensor has been utilized in numerous research studies around the world.

The IRROMETER Model “R” is the standard one-piece for general use with row, tree, and field crops.

Includes reservoir, air free gauge chamber and hermetically sealed vacuum gauge with dual scale of centibars and kilopascals (0-100 cb [kpa] range)
The IRROMETER Model “SR” has a threaded replaceable tip as well as all the features of the Model R above.

Includes reservoir, air free gauge chamber and hermetically sealed vacuum gauge with dual scale of centibars and kilopascals (0-100 cb [kpa] range)

The IRROMETER Model “S” – has a threaded connection at the top of the tube. Designed for research work where change in instrument length is required for different experiments, and or general use with row, tree, and field crops. When ordering, select Extention Tip(s) in combination with the Reservoir Selection.

Includes reservoir, air free gauge chamber and hermetically sealed vacuum gauge with dual scale of centibars and kilopascals (0-100 cb [kpa] range)

The IRROMETER Model “P” (Portable) – Unlike other model IRROMETERs which are intended for permanent installation, the Model “P” is designed to be installed in a temporary situation so that the user can make a “spot check” of soil water tension and then relocate the instrument to other locations. Each site reading may take from minutes to hours, depending on soil conditions.

Includes reservoir, air free gauge chamber and hermetically sealed vacuum gauge with dual scale of centibars and kilopascals (0-100 cb [kpa] range)

The IRROMETER Model “LT” (low tension) – is designed for situations where tensions above 30 cb (kPa) are rarely expected. Ideal for very coarse soils and non-soil container-media or where rapidly changing soil water status needs to be observed. Incorporates a replaceable Quick-Flo tip (blue color), and low tension vacuum gauge (40 cb).

Includes reservoir, air free gauge chamber and hermetically sealed vacuum gauge with dual scale of centibars and kilopascals (0-40 cb [kpa] range)

The IRROMETER Model “MLT” (Miniature Low Tention) – designed for appications similar to the Model “LT” above. Ideal for use with very coarse soils and non-soil container-media. Its compact size and replaceable “Quick-Flo” tip make it the best choice for green house applications.

The IRROMETER Model “TG” – for shallow rooted applications such as turf, where installation requires horizontal placement of the sensing tip.

Includes reservoir, air free gauge chamber and hermetically sealed  vacuum gauge with dual scale of centibars and kilopascals (0-100 cb [kpa] range)

The IRROMETER “Automation and Output Options” for the tensiometers are Gauges and or Transducers for direct switching capabilities.

These options provide automation for irrigation valves and electronic output for use with automatic data collection systems. They can be added at the factory when purchased or added to your existing instruments in the field (as accessory items).

To learn more about IRROMETER and their offerings, visit their website at http://www.irrometer.com/