What the soil tests found
6
out of 10
Soil score
OkayShort in most fields here: nitrogen, organic carbon, pH and iron.
For most crops. How the soil score works
- soil samples, 2023-24 & 2024-25
- 1,177
- nutrients checked in each sample
- 12
This shows what soil in this area tends to be like. Your own field can be different. Get it tested at a soil testing lab before deciding.
Nutrient by nutrient
-
Nitrogen
PoorLow 100%
Almost every soil test here came out low
If your field is low: add about a quarter more urea than the usual dose, in two or three splits. A pulse crop in rotation also adds nitrogen.
What this means
Grows leaves and stems. Short soil gives pale, yellow leaves.
Low under 280 kg/ha Medium 280–560 kg/ha High over 560 kg/haHealthy soil has 280 kg/ha or more.
Compared with the wider area Place Low Medium High Here 100% 0% 0% Namakkal 100% 0% 0% Tamil Nadu 99% 1% 0% India 64% 30% 6% -
Phosphorus
OkayLow 31% Medium 26% High 42%
3 in 10 soil tests here came out low
If your field is low: add about a quarter more DAP or single super phosphate than the usual dose, at sowing.
What this means
Builds roots and helps the crop flower and fill grain.
Low under 10 kg/ha Medium 10–25 kg/ha High over 25 kg/haHealthy soil has 10 kg/ha or more.
Compared with the wider area Place Low Medium High Here 31% 26% 42% Namakkal 22% 30% 48% Tamil Nadu 21% 43% 36% India 14% 41% 45% -
Potassium
GoodLow 9% Medium 38% High 53%
Most soil tests here came out high
If your field is high: you can use about a quarter less potash than usual.
What this means
Fills grain and fruit, and helps crops stand drought and disease.
Low under 110 kg/ha Medium 110–280 kg/ha High over 280 kg/haHealthy soil has 110 kg/ha or more.
Compared with the wider area Place Low Medium High Here 9% 38% 53% Namakkal 3% 20% 77% Tamil Nadu 11% 43% 46% India 14% 53% 34% -
Organic carbon
PoorLow 91% Medium 8% High 1%
9 in 10 soil tests here came out low
If your field is low: add 4 tonnes of compost or farmyard manure per acre before sowing, and plough crop leftovers back in instead of burning them.
What this means
Shows how much organic matter the soil has. It keeps soil loose, holds water and feeds the crop slowly.
Low under 0.5% Medium 0.5–0.75% High over 0.75%Healthy soil has 0.5% or more.
Compared with the wider area Place Low Medium High Here 91% 8% 1% Namakkal 89% 9% 2% Tamil Nadu 88% 9% 3% India 48% 28% 23% -
pH
PoorNeutral 48% Alkaline 52%
5 in 10 soil tests here came out alkaline
If your field is alkaline: add compost or farmyard manure. Very alkaline land also needs gypsum; a soil lab works out how much.
What this means
How sour (acidic) or alkaline the soil is. It decides which nutrients roots can take up.
Acidic Neutral AlkalineMost crops do best at pH 6.5 to 7.5.
Compared with the wider area Place Acidic Neutral Alkaline Here 0% 48% 52% Namakkal 3% 77% 21% Tamil Nadu 2% 93% 5% India 12% 86% 2% -
Salt
GoodNot salty 99% Salty 1%
Almost no soil tests here came out salty
What this means
Salt in the soil, shown as EC on the card. Salt makes it hard for roots to drink.
Not salty SaltyUnder 1 dS/m is fine. Above 4 harms most crops.
Compared with the wider area Place Not salty Salty Here 99% 1% Namakkal 98% 2% Tamil Nadu 98% 2% India 96% 4% -
Sulphur
OkayShort 26% Enough 74%
3 in 10 soil tests here came out short
If your field is short: use single super phosphate instead of DAP, or add about 100 kg of gypsum per acre before sowing.
What this means
Makes oil in oilseeds and protein in pulses.
Short under 10 ppm Enough 10 ppm or moreHealthy soil has 10 ppm or more.
Compared with the wider area Place Short Enough Here 26% 74% Namakkal 41% 59% Tamil Nadu 35% 65% India 24% 76% -
Zinc
OkayShort 31% Enough 69%
3 in 10 soil tests here came out short
If your field is short: mix 10 kg of zinc sulphate per acre into the soil before sowing. One dose lasts two or three seasons.
What this means
Needed for growth and healthy leaves. Rice and wheat often run short.
Short under 0.6 ppm Enough 0.6 ppm or moreHealthy soil has 0.6 ppm or more.
Compared with the wider area Place Short Enough Here 31% 69% Namakkal 49% 51% Tamil Nadu 42% 58% India 35% 65% -
Iron
PoorShort 74% Enough 26%
7 in 10 soil tests here came out short
If your field is short: spray ferrous sulphate, 5 g per litre of water, when young leaves turn yellow.
What this means
Keeps young leaves green.
Short under 4.5 ppm Enough 4.5 ppm or moreHealthy soil has 4.5 ppm or more.
Compared with the wider area Place Short Enough Here 74% 26% Namakkal 76% 24% Tamil Nadu 39% 61% India 24% 76% -
Copper
GoodShort 2% Enough 98%
Almost every soil test here had enough
What this means
Helps the crop set seed and resist disease.
Short under 0.2 ppm Enough 0.2 ppm or moreHealthy soil has 0.2 ppm or more.
Compared with the wider area Place Short Enough Here 2% 98% Namakkal 4% 96% Tamil Nadu 3% 97% India 5% 95% -
Manganese
OkayShort 30% Enough 70%
3 in 10 soil tests here came out short
If your field is short: spray manganese sulphate, 5 g per litre of water, on the young crop.
What this means
Helps leaves make food from sunlight.
Short under 2 ppm Enough 2 ppm or moreHealthy soil has 2 ppm or more.
Compared with the wider area Place Short Enough Here 30% 70% Namakkal 35% 65% Tamil Nadu 28% 72% India 13% 87% -
Boron
OkayShort 40% Enough 60%
4 in 10 soil tests here came out short
If your field is short: mix 4 kg of borax per acre into the soil before sowing.
What this means
Needed for flowers to set seed and fruit.
Short under 0.5 ppm Enough 0.5 ppm or moreHealthy soil has 0.5 ppm or more.
Compared with the wider area Place Short Enough Here 40% 60% Namakkal 43% 57% Tamil Nadu 45% 55% India 45% 55%
Fixes are the usual advice. Your Soil Health Card or nearest Krishi Vigyan Kendra gives the exact dose for your field.
Source: Soil Health Card – soil nutrient analysis (Ministry of Agriculture & Farmers Welfare). 2023-24 & 2024-25. 1,177 samples.
Climate in Namakkal
Rain
About 790 mm of rain a year
In a normal year. A dry year brings about 570 mm.
Temperature
Hottest in April: days about 36°, nights 24°
Coolest in January: days about 30°, nights 19°.
Averages for an area about 100 km across; hills and valleys can differ by several degrees.
Source: IMD gridded daily rainfall (0.25°); IMD gridded daily max/min temperature (1°).