From lab to farm: How Proximal Soilsens is developing a ‘glucometer’ for soil testing

Indian farmers are increasingly being encouraged to adopt balanced fertiliser use. However, access to timely and reliable soil testing remains limited in several regions. Despite its importance for soil health and farm productivity, testing infrastructure remains inadequate across large parts of the country. Pune-based agritech startup Proximal Soilsens is looking to bridge this gap by bringing laboratory-based soil analysis to the farm through a portable, sensor-based device.

Its flagship product, NutriSense X, is designed to measure soil nutrients and other parameters using a technology that founder Rajul Patkar describes as a "soil glucometer". The idea draws on the principle of blood glucose meters, which have made testing possible outside conventional pathology laboratories.

The innovation is significant, particularly in a country with a large farming population and limited testing infrastructure, say industry observers. “Soil testing is among the most under-served links in Indian agriculture. With roughly 14 crore farmers and only about 3,000 soil testing labs, most farmers apply fertiliser on habit rather than evidence, and that costs them in input spend, yields and long-term soil health. The opportunity is large: timely, affordable soil data can anchor everything from balanced nutrient use to regenerative practices and climate-smart advisory,” says Ajay Menon, Senior Practice Lead and Program Director, TechnoServe India, a global non-profit that works with smallholders farmers.


For Proximal Soilsens, the technology is the outcome of nearly a decade of research that began at the Indian Institute of Technology (IIT) Bombay in 2011. Patkar started working on agricultural sensors during his doctoral research in the institute's electrical engineering department under Professor Ram Gopal Rao.

The initial research received support from the Department of Science and Technology and involved several researchers and doctoral students. Mukul Singh, who subsequently joined the company, continued working on the technology alongside Patkar. Both are named inventors on the NutriSense X patent. “We were more focused on sensors and deep tech rather than building something immediately and taking it to market. Our aim was to develop something that was not already available in the market, rather than make an incremental improvement,” Patkar says.

How the testing process works

The central innovation behind NutriSense X lies in simplifying the conventional soil testing process without abandoning its chemical basis. In a laboratory, soil samples are mixed with chemical reagents to extract nutrients into a solution. Instruments such as spectrophotometers, flame photometers, pH meters and electrical conductivity meters are then used to analyse the extracted solution. Proximal SoilSens has worked to integrate this process into a portable sensor-based system. Instead of requiring a conventional laboratory setup, the device allows testing to be carried out closer to the farm.

The process begins with collecting a soil sample from the field and preparing it for testing. The sample is mixed with specially developed chemical reagents to extract the relevant nutrients into a solution. The prepared sample is then allowed to undergo a chemical reaction, which takes around 30-45 minutes. Users can attend to other tasks during this waiting period. Once the reaction is complete, the sample is tested using the device's sensor-based system. Each parameter takes approximately 15-20 seconds to measure. The overall testing time depends on the number of parameters being analysed. The device connects to a mobile phone, which also supplies its power and internet connectivity. Results can therefore be generated in the field without a conventional laboratory setup.

The company has developed the different components of the testing system, including the hardware, sensors, testing strips and chemical reagents. This integrated approach allows it to control the technology across the testing process. According to Patkar, NutriSense X can test parameters including pH, nitrate, phosphate, potassium, electrical conductivity and organic carbon. The company is also expanding its capabilities to include micronutrients and iron.

Designed around field conditions

A key consideration in the product's development has been usability outside a laboratory. Patkar says the company initially developed moisture sensors and Internet of Things-based solutions, but field deployment exposed limitations that were not apparent during laboratory testing. The company subsequently redesigned its products based on user feedback. Its portable moisture meter, TerraPoat, has also received an Indian patent.

NutriSense X has been designed to avoid the infrastructure requirements associated with conventional testing equipment. It weighs around 500 grams, compared with tabletop soil testing systems that can weigh about 20 kg. It does not require a battery or an external electricity connection and draws power from a connected mobile phone. The company has also sought to minimise the training required to operate the device. Patkar says users should ideally be able to learn the process within 30 minutes to an hour. The company's distribution model reflects this approach. Rather than expecting every farmer to purchase a testing device, Proximal Soilsens sees farmer producer organisations, self-help groups, village-level entrepreneurs and other institutions as potential service providers. "We believe that individual farmers should get a service. It is more suitable for an SHG (Self-Help Group), FPO (Farmer Producer Organisation) or a village-level entrepreneur to provide this service to farmers," Patkar says.

However, industry observers highlight that the challenge goes beyond making testing equipment portable. Farmers also need confidence in the results and the ability to translate them into decisions on nutrient application and soil management.

“The hard parts are reach, trust in results, and turning a reading into a decision a farmer will actually act on. Proximal Soilsens is tackling exactly this by moving testing from the lab to the field, with results in minutes rather than weeks, at a cost that works for rural agripreneurs. At Greenr, we see this kind of last-mile agri-tech as critical to making Indian farming both more profitable and more sustainable," adds Menon of TechnoServe India.

From research to commercial adoption

The transition from research to commercialisation began when Mahindra Group approached the IIT Bombay research team to pilot its technology. The engagement led to the incorporation of Proximal Soilsens in 2017 and an initial paid pilot worth around Rs 3.5 lakh. The company subsequently secured orders from Idian Council of Agricultural Research (ICAR) and Coromandel International, which also helped validate its technology through field deployments.

Detailing the outcomes of the pilots, Patkar says, “The pilots with organisations such as Mahindra and ICAR have helped us validate the technology under different field conditions and demonstrate its practical value. The deployments have recorded over 95% accuracy in results compared with conventional laboratory testing, demonstrating the reliability of the device in field applications. This is helping institutions provide farmers with timely and reliable soil data, enabling better-informed decisions on nutrient application and soil management. This can further translate into more balanced fertiliser application, better input-use efficiency and, where soil conditions permit, improvements in crop productivity. We now have active pilots and deployments across several states, including Maharashtra, Assam, Punjab, Telangana, Gujarat, Jharkhand, Madhya Pradesh and Rajasthan. The experience is helping us refine the technology and adapt it to different soil types.”

Unlike companies that initially concentrate on establishing a presence in a single geography, Proximal Soilsens has followed a demand-led expansion strategy. Its technology requires limited installation infrastructure and can be operated after relatively short training. The company says customer enquiries and orders have also come through platforms such as LinkedIn.

The company says its technologies have been adopted by more than 100 institutional customers, including agribusinesses, NGOs, farmer producer organisations, research institutions, universities, government agencies and soil testing service providers. Through these institutional users, its solutions have supported soil testing and advisory services for tens of thousands of farmers across India.

Proximal Soilsens currently reports annual turnover of approximately Rs 95 lakh and describes itself as being in a commercial growth phase. Patkar adds that the company has relied on grants, customer revenues and founder funding to sustain its research and product development. It has received grants amounting to around Rs 2 crore through programmes including BIRAC, Millennium Alliance, Social Alpha's Krishi Mangal and the Atal Innovation Mission. Rather than pursuing rapid expansion, the company has prioritised deep-tech development, product validation, intellectual property creation and institutional partnerships.

Building beyond soil testing

The company has largely relied on grants, customer revenues and founder funding rather than pursuing a high-burn expansion model. Patkar says he prefers building revenue through customer engagements while continuing to invest in research. Its technology has reached 16-17 states in India, with deployments involving foundations, institutions and industry organisations. The company has also supplied products to overseas customers, including in Indonesia. The next phase, Patkar says, will focus on expanding the company's sensor-based product portfolio beyond soil testing to include water quality monitoring and sap analysis, particularly for horticulture applications. She says this focus could be very relevant for the country's horticulture farmers. The company is also looking to deepen its presence in international markets, where it has already begun receiving orders. "Our aim is to build a wider portfolio of sensor-based solutions for agriculture. There are several areas, including water quality and sap analysis, where portable testing can make a difference. We want to continue building on our research capabilities and work with partners who can take these technologies further,” Patkar says.