Lucerne Fertilizer Calculator
Work out the exact urea, DAP and MOP for lucerne (alfalfa) from the recommended 20:80:40 kg/ha N-P₂O₅-K₂O dose, adjusted to your soil test and field size.
Heavy P + K with a small starter N at establishment; thereafter ~40 kg P2O5/ha annually after a major cut. A legume fed phosphorus rewards you in protein-rich fodder for 3–4 years.
Indicative planning figures based on published research averages. Local soil tests, varieties and weather change actual requirements — confirm with your agronomist or extension officer.
Farmers and agronomists use the free Lucerne Fertilizer Calculator to convert the official lucerne (alfalfa) recommendation into exact urea, DAP and MOP quantities for their own field in seconds — no agronomy tables, no spreadsheet, and it works offline in the field.
About Lucerne Fertilizer Calculator
Lucerne is a phosphorus story: the legume fixes its own N for years of fortnightly cuts, provided P (and on light soils K and S) keeps the nodulated stand vigorous. This calculator starts from the published recommendation of 20:80:40 kg/ha N-P₂O₅-K₂O (multi-cut perennial), adjusts it ±25% for your soil-test N, P and K ratings, scales it to your field area in hectares, acres or bigha, and converts the nutrients into real products — urea (46% N), DAP (18-46-0) and MOP (0-0-60) — including the number of bags to buy.
How to use Lucerne Fertilizer Calculator
- 1Enter your field area and pick the unit (hectare, acre or bigha).
- 2Choose the growing condition and your soil-test ratings for N, P and K — leave Medium if you have no recent soil test.
- 3Read off the urea, DAP and MOP quantities and bag counts, then follow the split-application note for timing.
Why use Lucerne Fertilizer Calculator?
- ✓Official package-of-practices dose for lucerne (alfalfa) — not a generic NPK guess
- ✓Soil-test Low/Medium/High ratings adjust the dose ±25% automatically
- ✓Converts nutrients to urea, DAP and MOP bags, with the DAP nitrogen credit handled correctly
- ✓Works in hectares, acres and bigha — and runs fully in your browser, even offline in the field
Frequently asked questions
What is the recommended fertilizer dose for lucerne (alfalfa)?+
Multi-cut perennial: 20 kg N, 80 kg P₂O₅ and 40 kg K₂O per hectare. Heavy P + K with a small starter N at establishment; thereafter ~40 kg P2O5/ha annually after a major cut.
How do I fertilize an established lucerne stand?+
Skip nitrogen — nodules supply it. Maintain with ~40 kg P2O5 (and 20–30 kg K2O on light soils) once or twice a year after cuts, plus gypsum where sulphur is low.
Why is my lucerne stand thinning after two years?+
Phosphorus exhaustion, waterlogging or cutting too low/too often are the usual culprits. Annual P maintenance and a 5–6 cm cutting height protect stand life.
How does the calculator convert NPK into urea, DAP and MOP?+
DAP (46% P₂O₅) is sized to cover the phosphorus need; the nitrogen it also carries (18% N) is credited against the N requirement, and urea (46% N) supplies the balance. MOP (60% K₂O) covers potassium. Bag counts use 45 kg urea and 50 kg DAP/MOP bags.
Is this tool free, and does my data leave the device?+
It is completely free with no sign-up, and all calculation happens in your browser — nothing you enter is uploaded, so it also works offline in the field.
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