These modernized tensiometers, built by German company UMS, are THE most accurate way to measure soil matric potential. Thanks to precision engineering, meticulous construction, and fanatical attention to detail, they have terrific accuracy and a range that (with a skilled operator) can extend beyond -200 kPa.
Tensiometers are by far the most accurate, precise and highest resolution instruments for measuring soil water potential in the wet end. UMS's line of tensiometers are engineered and produced with extreme tolerances, giving them the best performance characteristics of any tensiometers ever made.
Traditional tensiometers cavitate around -80 kPa. Fanatical attention to detail in design and manufacturing (along with a few mystical tricks of physics) have enabled UMS to build tensiometers that can go beyond -200 kPa.
Standard field tensiometer. Only the ceramic cup is filled with water to improve accuracy and offer year-round operation. Optionally with external refilling: The model T4e with external refilling can be refilled or emptied without removing it from the soil.
Quick-response mini-tensiometer for measuring water potential in small spaces like soil columns, potted plants, and laboratory water flow experiments. Can be used to make spot measurements in the field if care is used.
Field tensiometer's water level indicator tells you when to refill. Also measures temperature and has an external refilling option.