Claims checked › Claim
Smart irrigation saves 30% of your water
“Fitting soil moisture sensors and a scheduling platform cuts your irrigation water use by 20 to 30%.”
An advisory body traces that range to the suppliers themselves. The measured European results are 24% one year and 6% the next in the same olive orchard, and 10% then 17% in an Italian vineyard. The percentage is against your own baseline, which most farms have never metered.
Where it comes from
Supplier and platform marketing. Scotland's Farm Advisory Service puts it plainly: "commercial suppliers often report water savings of 20–30 percent with well-managed systems" (FAS Scotland). The figure is repeated in trade press and in the case studies on vendor websites.
Who benefits
Probe manufacturers, telemetry providers and subscription platforms, in a market where the buyer usually cannot check the claim because the farm never measured what it applied before.
What the evidence says
The measured European savings swing wildly between seasons. In a commercial super-high-density olive orchard at Alvarado in Extremadura, Spain, an automatic platform combining a water balance with soil-moisture feedback was run against expert-supervised scheduling for two seasons (Sensors):
| Season | Supervised | Automatic, sensor-corrected | Saving |
|---|---|---|---|
| 2016 | about 298–306 mm | about 198–232 mm | about 24% |
| 2017 | about 434–435 mm | about 405–444 mm | about 6% |
Yields were comparable in both years. The same equipment, the same orchard, the same operators, and the saving moved by a factor of four.
A second European trial lands lower. On a commercial Montepulciano vineyard at Andria in southern Italy, a soil-moisture decision-support system saved 10% and 17% of irrigation water across 2019 and 2020 against the farm's own scheduling, with "slight or no significant differences" in yield and none in quality (Agronomy 13(11):2821).
The percentage is against your baseline, not against good practice. A farm that has been over-irrigating will save a lot. A farm already scheduling well will save little, and the studies above compared sensors against expert scheduling, not against guesswork. Most farms have never metered what they apply, so they cannot tell which they are.
And a probe can make it worse. The same advisory body warns that generic calibration curves may not suit a given soil, so poorly installed or calibrated sensors "can produce misleading readings and result in irrigation scheduling that is no better, or potentially worse, than working without sensors".
Nobody has published what it costs in Europe. We found no independent European figure for probes, telemetry, installation or subscription per hectare, so the saving cannot be set against the spend.
What to say instead
"Meter what you apply first, then expect a saving somewhere between nothing and a quarter, different every season." Before buying, check whether your region publishes the same daily number for free: the precision irrigation page lists the Spanish, Italian and Portuguese services that do.