18-06-2025
Lack of awareness, limited facilities affect soil testing in Tamil Nadu's delta region
Soil testing, a vital scientific process to determine micro-nutrient levels and guide fertiliser use, remains underutilised in the delta districts of Tamil Nadu.
Despite repeated government campaigns, a combination of limited testing infrastructure and low farmer awareness continues to affect soil health and crop productivity across this crucial agricultural belt.
'There's no other way to assess nutrient levels except by testing,' said A. Anuratha, Associate Professor of Soil Science at the Agricultural College and Research Institute, Kilvelur. 'Just like we go for regular health check-ups, the soil must be tested seasonally. In Nagapattinam, for instance, salinity is steadily increasing. Overuse or incorrect use of fertilisers only degrades soil further and affects yield,' she explained.
K. Coumaravel, Associate Professor of Soil Science in PAJENCOA & RI, noted that 'at the global level, indicators show consistent deterioration in soil health due to climate change and unscientific farm practices. Knowing the micronutrient profile can help correct deficiencies that limit crop potential.'
Last State-wide soil sampling in 2018
Although both the Union government's Soil Health Card (SHC) programme and Tamil Nadu's Tamil Mann Valam portal aim to promote testing, field-level implementation remains inadequate. Official targets for SHC distribution are set annually, but large sections of the farming population remain outside its coverage as getting an SHC has not been made mandatory. According to government data, just 7,900 cards were generated in Nagapattinam and 7,350 in Mayiladuthurai for 2024-25—numbers that fall far short of total cultivators who have not got SHC's.
Experts point out that while the Tamil Mann Valam portal includes soil data for each village, most of it is not precise. The last State-wide mass soil sampling was conducted in 2018–19. 'Unless regular fresh surface samples are tested in labs, we cannot get accurate results,' said a soil scientist, adding that online records alone cannot replace lab analysis.
Only five soil labs
However, with only five labs and just two mobile testing units for the entire delta region, many farmers are unable to access timely services. Mayiladuthurai district has no lab of its own and must rely on Nagapattinam's.
'Even drinking water has turned saline,' said Vellamperambur Durai Ramesh, of the Cauvery Urimai Meetpu Kuzhu. 'Several villages in Thanjavur and Thiruvaiyar now report poor water-soil integration. Village-level soil testing is essential—we can't travel to town every time, and most farmers still apply fertilisers by guesswork.'
Vayalur N. Rajendran, Treasurer of the Farmers' Wing of Tamil Maanila Congress, added, 'Even when farmers get test results, the advisory is weak. Key micronutrients are not stocked in government co-operatives, forcing farmers to tap private markets. Testing alone is not enough—follow-up support must be ensured.'
In Tiruchi, agricultural officer M. Nagaraj from the Soil Testing Centre said awareness was growing among farmers, particularly those interested in fruit cultivation and plantations. 'Many now voluntarily bring in elite soil samples for analysis,' he said. At just ₹30 per sample, the tests provide clear and actionable results.
