Sensor-Based Irrigation: Can Farmers Save Groundwater by Watering Only When Crops Need It?

Farmers often irrigate crops according to a fixed schedule, even when soil moisture is still sufficient. Sensor-based irrigation offers another approach. It uses information about soil moisture and crop conditions to help farmers decide when irrigation is actually required.

ICAR-Central Research Institute for Jute and Allied Fibres recently trained farmers in West Bengal on sensor-based water management in jute-based cropping systems. The September 8–10 programme involved 80 farmers from 11 villages and focused on need-based irrigation, groundwater conservation and better crop productivity.

How Sensor-Based Irrigation Works

Soil moisture sensors measure the amount of water available in the soil. Farmers can use this information to decide whether irrigation is required instead of watering automatically at fixed intervals. The approach can be particularly useful where groundwater is limited or irrigation costs are rising.

The exact sensor and irrigation method can vary between farms. Some systems provide direct soil-moisture readings, while more advanced systems can connect sensors with controllers or mobile platforms. Farmers should select equipment according to crop, soil, irrigation method and available technical support.

During the recent ICAR-CRIJAF training, scientists encouraged farmers to move away from indiscriminate and conventional irrigation practices towards scientific, need-based water management. The institute highlighted groundwater as a finite resource and linked better irrigation decisions with water conservation and crop performance.

Farmers should also remember that soil moisture is only one part of irrigation planning. Crop growth stage, rainfall, temperature, soil type and weather conditions also affect water requirements. Sensor readings become more useful when farmers combine them with crop knowledge and local agricultural advice.

The main purpose of sensor-based irrigation is to avoid unnecessary watering. If soil moisture is already adequate, farmers can delay irrigation until the crop actually requires more water. This can reduce the number of irrigation events and help conserve groundwater.

ICAR has developed several technologies related to sensor-based irrigation. Its landmark technologies include an IoT-enabled soil-moisture sensing system for irrigation scheduling, which reported 10–15% water savings compared with traditional scheduling under the tested conditions.

Another ICAR technology uses sensor-based micro-irrigation scheduling in drip-irrigated banana. The system was reported to save about 20% water while increasing yield by 15% under the tested conditions. These results are technology-specific and should not be treated as guaranteed savings for every farm.

Water savings also depend on the irrigation system itself. A sensor cannot compensate for leaking pipes, blocked emitters or poorly designed irrigation networks. Farmers need to maintain their equipment and ensure that water reaches the crop evenly.

Why Groundwater Matters

Groundwater supports irrigation across large parts of Indian agriculture. When farmers repeatedly irrigate without checking crop or soil requirements, unnecessary pumping can increase pressure on local water resources and raise electricity or diesel costs.

The recent ICAR-CRIJAF programme specifically focused on judicious use of groundwater in jute-based cropping systems. Scientists stressed that irrigation should be applied only when and where required rather than following fixed schedules throughout the crop cycle.

Farmers can combine sensor-based irrigation with other water-saving practices. Drip irrigation, mulching, rainwater harvesting and suitable crop planning can reduce water demand. The right combination will depend on soil type, crop, rainfall and the availability of irrigation water.

ICAR and the International Water Management Institute also signed a five-year strategic work plan in September 2026 to strengthen research on climate-resilient agricultural water management. The plan covers scientific research and policy approaches aimed at improving water resilience in agriculture.

Sensor-based irrigation can be useful for farmers growing crops where irrigation timing has a significant effect on production. Horticultural crops, vegetables and crops grown under drip irrigation may particularly benefit because water can be delivered more precisely.

The technology can also be tested in jute-based systems. ICAR-CRIJAF’s recent training shows that sensor-based water management is being introduced to farmers beyond high-value horticulture, with a focus on improving irrigation decisions in field crops.

Small farmers do not necessarily need to install an expensive automated system immediately. A basic soil-moisture monitoring device can be used to understand field conditions before investing in more advanced equipment. Farmers can also explore shared equipment through farmer groups, FPOs or local agricultural programmes.

The cost of the technology should be compared with potential savings in water, electricity, diesel and labour. A system that is expensive to maintain may not be suitable for a small farm unless it provides enough savings or productivity benefits.

What Farmers Need Before Installing Sensors

Farmers should first understand their soil and irrigation system. Soil type affects how quickly water moves and how long moisture remains available to crops. Sandy soil may require different irrigation management from heavier soils, even when the same crop is grown.

The next step is choosing the right sensor. Farmers should check measurement range, durability, maintenance requirements, installation depth and compatibility with their irrigation system. Local KVKs and agriculture departments can help farmers identify suitable equipment.

Farmers should also avoid placing a sensor in only one location and assuming it represents the entire field. Soil conditions can vary within the same farm. Proper placement is important, particularly in larger or uneven fields.

Weather information can further improve decisions. If rain is expected, farmers may be able to postpone irrigation. During hot and dry periods, crops may lose water more quickly. Combining sensor readings with weather information can provide a better basis for deciding when to irrigate.

Can It Help Climate-Smart Farming?

Changing rainfall patterns and longer dry spells can make irrigation planning more difficult. Sensor-based irrigation cannot prevent drought, but it can help farmers use available water more carefully by reducing irrigation that is not needed.

ICAR’s recent work on climate-resilient water management also reflects the growing need to connect farm water decisions with changing climate conditions. Better measurement and need-based irrigation can form part of a wider strategy for protecting limited water resources.

For farmers, the practical starting point is simple: identify how much water the crop currently receives, check the soil moisture before irrigation and compare the cost of a sensor system with possible savings.

Sensor-based irrigation is not about watering crops less at all times. It is about watering them according to actual need. When combined with suitable irrigation equipment, weather information and crop-specific guidance, the technology can help farmers reduce unnecessary water use while maintaining better control over irrigation.

As groundwater pressure grows and rainfall becomes less predictable, better irrigation decisions will become increasingly important. Farmers do not necessarily need a fully automated farm to begin. Even simple soil-moisture monitoring can provide useful information for deciding when the next irrigation is actually needed.