Tensiometers for Precision Irrigation

Choose by the depth of the active root zone. The SR (short range) suits shallow-rooted vegetables, flowers, turf, and greenhouse beds at 15-30 cm. The MLT (mid-length) covers field crops and orchards at 45-60 cm. The LT (long tube) reaches the deep root zone of orchards and vineyards at 90-120 cm. Many operations place more than one depth per station to see the full moisture profile.

A tensiometer measures soil water tension directly with a water-filled tube and reads accurately in the wet range, but the tube needs periodic refilling. A granular matrix sensor like the Watermark 200SS is maintenance-free, covers a wider 0-200 cb range, and lasts multiple seasons, at a coarser accuracy. Tensiometers are the choice for precise wet-range irrigation; the Watermark is the choice when low maintenance and a wide range matter more.

Install the sensing tip at the depth where the crop draws most of its water. Shallow vegetables and turf are read at 15-30 cm, field crops and orchards at 45-60 cm, and deep-rooted trees and vines at 90-120 cm. A second, deeper station is useful to confirm that water is reaching, and not passing below, the root zone.

Yes. A tensiometer holds water in its tube and needs periodic refilling and servicing, especially after the soil dries past the point where the tube can hold vacuum. If maintenance-free operation is the priority, the Watermark 200SS granular matrix sensor provides soil tension data without the refilling routine.

Yes. Connected to an Agrinovo Genesis controller, a tensiometer reading drives closed-loop irrigation: when tension rises past your dry threshold the controller opens the valve, and when it falls past the wet threshold it closes. Readings, alerts, and automation run through the IoT soil monitoring platform.

The price depends on the tube length (SR, MLT, or LT), whether you read it manually from the gauge or connect it to a controller for continuous logging, and how many stations your plot needs. Our pricing is by tailored quotation, so you pay for the configuration that fits your field rather than a generic bundle. Request a quote with your crop and plot details and we will come back with a concrete recommendation.

The practical rule: one measurement station per homogeneous irrigation zone (same crop, same soil type, same drip line), usually with two depths per station: one in the heart of the root zone and one below it to check for deep percolation. Start with one or two stations in the most representative zones and expand after a season, once you see where the real variability is.

Tensiometers work in most agricultural soils. In fast-draining sandy soil tension changes quickly, so frequent reading matters (an advantage for controller-connected units); in heavy soil the changes are slower. The 0-80 centibar range covers the irrigation decision range for most crops; for soils managed unusually dry, consider a granular matrix sensor with a wider range.

Many years, given simple seasonal maintenance: refilling the fluid at the start of the season, checking vacuum, and keeping the ceramic tip wet. At the end of the season, remove, rinse, and store with the ceramic tip protected. The tube and gauge are simple mechanical components with no field-degrading electronics.