Purnia

Most soil here is low in nitrogen. Maize and rice cover the most farmland.
Soil score
8/10
Good for most crops
Rain
1,540 mm
a year, most of it May⁠–⁠Sep
Temperature
10°–34°
Hottest in April, coolest nights in January
Main crop
Maize
87,722 ha sown

Soil

What soil tests across the district found, nutrient by nutrient.

8

out of 10

Soil score

Good

Short in most fields here: nitrogen.

For most crops. How the soil score works

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.

  • Nitrogen

    Poor

    Low 60% Medium 40%

    6 in 10 soil tests 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 LowMediumHigh
    Here 60% 40% 0%
    Bihar 62% 37% 1%
    India 64% 30% 6%
  • Phosphorus

    Good

    Low 5% Medium 20% High 75%

    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 LowMediumHigh
    Here 5% 20% 75%
    Bihar 3% 21% 76%
    India 14% 41% 45%
  • Potassium

    Good

    Low 5% Medium 63% High 32%

    Almost every soil test here had enough

    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 LowMediumHigh
    Here 5% 63% 32%
    Bihar 6% 72% 22%
    India 14% 53% 34%
  • Organic carbon

    Okay

    Low 37% Medium 48% High 14%

    4 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 LowMediumHigh
    Here 37% 48% 14%
    Bihar 33% 53% 14%
    India 48% 28% 23%
  • pH

    Okay

    Acidic 20% Neutral 79%

    2 in 10 soil tests here came out acidic

    If your field is acidic: add agricultural lime before sowing. A soil lab works out how much your field needs.

    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 AcidicNeutralAlkaline
    Here 20% 79% 0%
    Bihar 3% 96% 1%
    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 saltySalty
    Here 98% 2%
    Bihar 99% 1%
    India 96% 4%
  • Sulphur

    Okay

    Short 28% Enough 72%

    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 more

    Healthy soil has 10 ppm or more.

    Compared with the wider area
    Place ShortEnough
    Here 28% 72%
    Bihar 22% 78%
    India 24% 76%
  • Zinc

    Okay

    Short 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 more

    Healthy soil has 0.6 ppm or more.

    Compared with the wider area
    Place ShortEnough
    Here 31% 69%
    Bihar 23% 77%
    India 35% 65%
  • Iron

    Good

    Enough 100%

    Almost every soil test here had enough

    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 ShortEnough
    Here 0% 100%
    Bihar 7% 93%
    India 24% 76%
  • Copper

    Good

    Enough 100%

    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 more

    Healthy soil has 0.2 ppm or more.

    Compared with the wider area
    Place ShortEnough
    Here 0% 100%
    Bihar 2% 98%
    India 5% 95%
  • Manganese

    Good

    Short 5% Enough 95%

    Almost every soil test here had enough

    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 ShortEnough
    Here 5% 95%
    Bihar 5% 95%
    India 13% 87%
  • Boron

    Okay

    Short 31% Enough 69%

    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 ShortEnough
    Here 31% 69%
    Bihar 38% 62%
    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. 23,219 samples.

Climate

Rain and temperature through the year, from 24 years of weather records.

Rain

About 1,540 mm of rain a year

In a normal year. A dry year brings about 1,320 mm.

Temperature

Hottest in April: days about 34°, nights 22°

Coolest in January: days about 22°, nights 10°.

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°).

Crops that suit Purnia

Judged on the soil, rain and temperature here, whether or not they're grown here now. Best bets first: what each could earn an acre before costs, with risky crops moved down.

What grows here

Each crop's share of the district's farmland in recent years, with its yield. Tap a crop to see it across India.

Yield against other districts

Maize

Yield is better than 97% of districts growing it.

Rice

Yield is better than 28% of districts growing it.

Wheat

Yield is better than 56% of districts growing it.

0.0 4.7 9.3
1997-98 2024-25
Latest 7.8 t/ha in 2024-25

Source: Crop area, production & yield – district-wise (Ministry of Agriculture & Farmers Welfare); Crop area, production & yield – UPAG (Ministry of Agriculture & Farmers Welfare). 2016-17 to 2024-25.

Compared with similar soil

What this district harvests, next to districts whose soil tests look alike.

Maize

Here 8.1 t/ha
Similar soil 4.7 t/ha

Districts with similar soil typically get 4.7 t/ha of maize; here it's 8.1 t/ha.

Rice

Here 2.1 t/ha
Similar soil 2.2 t/ha

Districts with similar soil typically get 2.2 t/ha of rice; here it's 2.1 t/ha.

Wheat

Here 3.1 t/ha
Similar soil 2.9 t/ha

Districts with similar soil typically get 2.9 t/ha of wheat; here it's 3.1 t/ha.

Yields also depend on water, weather, seeds and farming practice, not only soil.

Source: Soil Health Card – soil nutrient analysis (Ministry of Agriculture & Farmers Welfare); Crop area, production & yield – district-wise (Ministry of Agriculture & Farmers Welfare); Crop area, production & yield – UPAG (Ministry of Agriculture & Farmers Welfare).

Who farms here

Farms
3.8 lakh
Average farm size
0.5 ha
Young farmers (18–30)
2%
Farmers with secondary school or more
22%
Farmland that is irrigated
80%
Farmers who took a bank or co-op loan
4%
Farmers who had their soil tested
1%
Farmers using certified seed
21%
Drip or sprinkler sets per 1,000 farms
0

Source: Agricultural Input Survey (Ministry of Agriculture & Farmers Welfare). 2016-17.

Districts with similar soil

Places whose soil tests look most like this district's, and what they grow.

Blocks in this district

Open a block for its soil report and the villages in it.