Sensors on the farm
Farmers and growers make decisions every day about water, weather and crops in store.
A sensor can put a number on some of those decisions. This page covers what the common ones measure and a few things to check before you buy.
Whether water is the limit
The Agriculture and Horticulture Development Board (AHDB) says light limits the growth of grass and many combinable crops in the UK more often than water does, apart from short spells.
Potatoes and many vegetable crops are a different case. Growers often irrigate them because the crop needs more water than the rain supplies. High-yielding crops also run a higher risk of running short.
Soil moisture sensors
Some growers use a reading called soil matric potential to help decide when to irrigate. AHDB puts the water that plants can readily use in the range of -10 to -100 kilopascals.
Growers also judge it by hand, from the look and feel of soil lifted with an auger. A probe gives a measured reading instead.
AHDB points out a bonus of installing probe access tubes. The grower may find compacted layers in the soil on the way down.
Weather stations
A farm weather station records the weather where your crops are. The government's grant specification for one asks it to record air pressure, temperature, humidity, rainfall, and wind speed and direction. It also asks for UV light, soil moisture and soil temperature, sent wirelessly to a computer.
That grant left out installation, servicing and the yearly software licence. Ask a supplier about those costs too.
Sensors in the crop store
A crop store system watches the air around stored crops. The grant specification for one asks for sensors for temperature and humidity inside and outside the store, and two for carbon dioxide.
Signal in the field
Remote sensors pass their readings to a base station or a phone. If yours relies on the mobile network, Ofcom's mobile coverage checker shows, by postcode, whether 4G or 5G is available indoors or outdoors.
Water for irrigation
In England, a farm that takes more than 20 cubic metres of water a day from a river, stream, canal or groundwater needs an abstraction licence from the Environment Agency. That is 20,000 litres.
If a farm takes water from the same source at several points, the 20 cubic metre limit applies to the total.
Grants for sensors
The 2026 Farming Equipment and Technology Fund in England listed several sensors. They included a digital weather station, remote soil moisture sensing and a soil health kit with a pH meter, penetrometer and soil moisture meter.
Items had to be new or ex-display, and the farm had to keep them for five years. Subscriptions and software were left out of the soil moisture item. The 2026 window closed at midday on 12 May 2026.