Manure Application Rate & How Much Per Acre?
Spreads FYM
Pick your manure, set a target nitrogen, and get the tonnes per acre to apply, the field total, and the N, P₂O₅ and K₂O it supplies — with a phosphorus-loading check.
Manure & field
High phosphorus loading — don't repeat every year on the same field.
Next: spread 40 t/ha and incorporate within a day to save N; top up any remaining N with a small urea dose if needed.
N/P/K and availability are typical values (ICAR/extension) — test your manure for exact content.
Manure application rate — key facts
- Available N/t
- 1000 × N% × availability
- Rate
- target N ÷ available N per tonne
- FYM availability
- ≈ 30% in year one
- Poultry availability
- ≈ 60% in year one
- Also supplies
- P₂O₅ and K₂O
- Incorporate
- within a day to save N
- Watch
- phosphorus build-up over years
- Privacy
- Runs in your browser; nothing uploaded
Turn manure into a measured nutrient plan
Manure is valuable fertiliser and a soil-builder, but spread by guesswork it either falls short or piles on more phosphorus than the land can use. The key is that only part of its nitrogen is available the first year, so the right rate is based on available N — not the raw percentage. Get that right and manure can carry most of a crop's nutrition while improving structure, water holding and soil life.
This tool gives the tonnes per acre or hectare to meet your nitrogen target, the field total, and the N, P₂O₅ and K₂O supplied, and warns when phosphorus loading is high. Use it to cut your fertiliser bill, plan where manure goes, and avoid building up soil P. Pair it with the Fertilizer (NPK), Compost & Manure and Nutrient Use Efficiency tools for a complete nutrient plan.
Right rate, not guesswork
Tonnes per acre based on available nitrogen.
Cut fertiliser cost
Count the P and K the manure already supplies.
Protect the soil
Avoid phosphorus build-up and runoff risk.
Plan the field total
Know the tonnes to cart and spread.
Frequently Asked Questions
How much manure should I apply per acre?+
It depends on the manure's nitrogen content, how much of that nitrogen becomes available in the first year, and your target N. The tool divides your target nitrogen by the available nitrogen per tonne to give the tonnes per acre (or hectare). For FYM at a 60 kg N/ha target, that's often around 16 t/acre.
Why do I need more manure than the nitrogen percentage suggests?+
Because only part of a manure's nitrogen is released in the first season — the rest is locked in organic matter and mineralises slowly over later years. The availability factor (about 30% for FYM, up to 60% for poultry) accounts for this, so the rate is based on year-one available N, not total N.
What is the availability factor?+
It's the fraction of a manure's total nitrogen that becomes plant-available in the first year. Fresh, low-N manures like FYM release slowly (~30%); nutrient-rich, fast-breaking ones like poultry manure release more (~60%). The tool uses typical factors; warm, moist, well-incorporated soils release more.
Does manure also supply phosphorus and potassium?+
Yes — at the rate needed to meet nitrogen, manure also delivers phosphorus (as P₂O₅) and potassium (as K₂O), which are largely available. The tool shows all three so you can reduce or skip your P and K fertiliser accordingly. Often the P and K from manure already meet or exceed crop needs.
What is the phosphorus-loading warning?+
Manure carries a lot of phosphorus relative to its nitrogen. Applying enough manure to meet a crop's nitrogen can supply far more phosphorus than the crop removes, and repeating it every year builds up soil P and risks runoff pollution. The warning flags when the P supplied is high so you rotate manure use or apply on a P basis.
Should I apply manure on a nitrogen or phosphorus basis?+
Nitrogen-based rates (what this tool gives) maximise the fertiliser value of the manure but can over-apply phosphorus over time. On fields already high in P, switch to a phosphorus-based rate (less manure) and top up nitrogen with a small mineral dose. Rotate where manure goes to spread the P load.
How do I get the most nitrogen from manure?+
Incorporate it into the soil within a day of spreading — surface manure can lose half its available nitrogen as ammonia to the air. Apply close to the time the crop needs N, keep it covered while stored, and avoid spreading before heavy rain that washes nutrients away.
Can I use this for any manure or area unit?+
Yes — pick from FYM, poultry, vermicompost, compost, goat/sheep manure or cattle slurry, and enter the area in acres, hectares, guntha, bigha or m². For a manure not listed, choose the closest type; for best accuracy, have your manure analysed for its actual N-P-K.
Does manure replace chemical fertiliser entirely?+
It can supply a large share of crop nutrients plus organic matter that improves soil structure, water holding and biology — but matching exact nitrogen timing for high-demand crops can need a small mineral top-up. Use manure as the base and fine-tune with fertiliser; see the Fertilizer (NPK) and Compost & Manure tools.
Are the nutrient values reliable?+
The N-P-K percentages and availability factors are typical published values (ICAR/extension) good for planning. Real manure varies widely with animal, bedding, storage and moisture, so a manure test gives the most accurate rate. Use this tool to get close, then adjust.