Thiruvallur

• Nitrogen

  Poor
  Low 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/ha

  Healthy soil has 280 kg/ha or more.

  Compared with the wider area

  Place	Low	Medium	High
  Here	100%	0%	0%
  Tamil Nadu	99%	1%	0%
  India	64%	30%	6%

• Phosphorus

  Good
  Low 13% Medium 26% High 62%

  Most soil tests here came out high

  If your field is high: you can use about a quarter less DAP than usual.

  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/ha

  Healthy soil has 10 kg/ha or more.

  Compared with the wider area

  Place	Low	Medium	High
  Here	13%	26%	62%
  Tamil Nadu	21%	43%	36%
  India	14%	41%	45%

• Potassium

  Okay
  Low 33% Medium 58% High 9%

  3 in 10 soil tests here came out low

  If your field is low: add about a quarter more potash (MOP) than the usual dose.

  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/ha

  Healthy soil has 110 kg/ha or more.

  Compared with the wider area

  Place	Low	Medium	High
  Here	33%	58%	9%
  Tamil Nadu	11%	43%	46%
  India	14%	53%	34%

• Organic carbon

  Poor
  Low 96% Medium 4% High 1%

  Almost every soil test 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	96%	4%	1%
  Tamil Nadu	88%	9%	3%
  India	48%	28%	23%

• pH

  Good
  Acidic 13% Neutral 87% Alkaline 1%

  1 in 10 soil tests here came out acidic

  What this means

  How sour (acidic) or alkaline the soil is. It decides which nutrients roots can take up.

  Acidic Neutral Alkaline

  Most crops do best at pH 6.5 to 7.5.

  Compared with the wider area

  Place	Acidic	Neutral	Alkaline
  Here	13%	87%	1%
  Tamil Nadu	2%	93%	5%
  India	12%	86%	2%

• Salt

  Good
  Not salty 98% Salty 2%

  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 Salty

  Under 1 dS/m is fine. Above 4 harms most crops.

  Compared with the wider area

  Place	Not salty	Salty
  Here	98%	2%
  Tamil Nadu	98%	2%
  India	96%	4%

• Sulphur

  Poor
  Short 61% Enough 39%

  6 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 more

  Healthy soil has 10 ppm or more.

  Compared with the wider area

  Place	Short	Enough
  Here	61%	39%
  Tamil Nadu	35%	65%
  India	24%	76%

• Zinc

  Okay
  Short 27% Enough 73%

  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 more

  Healthy soil has 0.6 ppm or more.

  Compared with the wider area

  Place	Short	Enough
  Here	27%	73%
  Tamil Nadu	42%	58%
  India	35%	65%

• Iron

  Poor
  Short 65% Enough 35%

  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 more

  Healthy soil has 4.5 ppm or more.

  Compared with the wider area

  Place	Short	Enough
  Here	65%	35%
  Tamil Nadu	39%	61%
  India	24%	76%

• Copper

  Good
  Short 6% Enough 94%

  1 in 10 soil tests here came out short

  What this means

  Helps the crop set seed and resist disease.

  Short under 0.2 ppm Enough 0.2 ppm or more

  Healthy soil has 0.2 ppm or more.

  Compared with the wider area

  Place	Short	Enough
  Here	6%	94%
  Tamil Nadu	3%	97%
  India	5%	95%

• Manganese

  Poor
  Short 81% Enough 19%

  8 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 more

  Healthy soil has 2 ppm or more.

  Compared with the wider area

  Place	Short	Enough
  Here	81%	19%
  Tamil Nadu	28%	72%
  India	13%	87%

• Boron

  Okay
  Short 34% Enough 66%

  3 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 more

  Healthy soil has 0.5 ppm or more.

  Compared with the wider area

  Place	Short	Enough
  Here	34%	66%
  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.