Sulphur (S) in crops: role, deficiency signs and how to correct it

Sulphur is a secondary nutrient the crop needs to build proteins, to make oil in oilseeds, to form chlorophyll and to use nitrogen well. A sulphur-short crop turns pale yellow from the young leaves, including the veins, and grows thin and weak. Sulphur shortage is the most widespread nutrient shortage in Indian soil tests, partly because urea and DAP carry no sulphur.

By Gafar Laiya and the Gujarat Bio Organics team. Updated November 2026.

What sulphur does in the plant

• Part of the amino acids cysteine and methionine, and so of every protein.
• Needed for oil formation in mustard, groundnut, soybean and sesame.
• Needed for chlorophyll formation.
• Helps nodules fix nitrogen in legumes.
• Gives onion and garlic their flavour and pungency.
• Helps the crop use the nitrogen it is given.

How sulphur moves in the plant

Sulphur moves only slowly from old leaves, so the shortage usually shows on young leaves first, unlike nitrogen, which shows on old leaves.

Signs of sulphur deficiency

• Young leaves turn pale yellow, including the veins, while old leaves may stay greener.
• Thin, spindly, upright plants.
• Delayed maturity.
• Low oil content in oilseeds, low protein in grain.
• Poor nodulation in legumes.

Crop by crop

More crops and look-alikes: Sulphur deficiency symptoms crop by crop.

Where and why it happens

In India, an ICAR survey of more than two lakh soil samples found 58.6% of soils short of sulphur, counting hidden shortages.

• Use of urea, DAP and MOP, which carry no sulphur, in place of single superphosphate and ammonium sulphate.
• Soils low in organic matter.
• Sandy, leached soils.
• Intensive cropping with high-yield varieties.
• Little use of farmyard manure.

How it works with other nutrients

• Nitrogen and sulphur work together: without sulphur, extra nitrogen is wasted.
• Sulphate competes with molybdenum and selenium uptake.
• Elemental sulphur slowly acidifies soil, which can help micronutrient availability in alkaline soils.
• See nutrient interactions.

What happens if it is not managed

• Lower yields and poorer quality: less oil, less protein, less flavour.
• Poor nitrogen use, so more urea for the same growth.
• Weaker legumes that fix less nitrogen.
• See the full picture of what unmanaged shortages cost.

How to confirm it

• Look at young leaves: pale yellow including the veins points to sulphur.
• Compare with nitrogen, which yellows the old leaves first.
• Ask for an available sulphur soil test, part of the Soil Health Card test.
• A leaf test confirms.

How to correct it

• Gypsum supplies sulphur and calcium.
• Single superphosphate supplies phosphorus and sulphur.
• Ammonium sulphate supplies nitrogen and sulphur.
• Bentonite or elemental sulphur supplies sulphur slowly and lowers pH a little in alkaline soils.
• Farmyard manure and compost supply sulphur over time.
• Take the dose from your soil test report, the product label or your agriculture officer.

Too much sulphur

• Sulphur excess is uncommon from fertilizers.
• Very heavy elemental sulphur can make soil too acid.
• Sulphate salts add to salinity in saline soils.

Doses depend on the crop, soil and product, so this page gives methods, not amounts. Take the dose from your soil test report, the product label or your local agriculture officer or KVK. Results differ from farm to farm with soil, weather, crop and management. Farmer experiences on this site are their own reports, not a promise of results.