Questions farmers ask us

With the standard agronomic formula: fertilizer (kg) = (nutrient needed × 100) ÷ nutrient % in the fertilizer. We apply it DAP-first — phosphorus from DAP, then the remaining nitrogen from urea (accounting for DAP's 18% nitrogen), then potassium from MOP — and show every step.

Acre, kanal, marla and hectare. Conversions used: 1 acre = 8 kanal = 160 marla, 1 kanal = 20 marla, 1 hectare = 2.471 acres.

Published provincial and research-institute recommendations (e.g. PAU package of practices), region-tagged. Every figure in the calculator carries its source citation, and crops without a verified source are marked 'data in review' rather than guessed.

No. It gives AI-assisted possibilities with uncertainty wording, but you should always confirm with your local agriculture officer before treating a crop — especially before spraying anything.

Yes — the calculator, libraries and guides are free. An account is only needed for features like saving diagnoses.

Yes, urea and DAP can be applied together as a basal dose at sowing. DAP provides phosphorus (46% P₂O₅) plus 18% nitrogen, while urea adds more nitrogen (46% N). A common practice is to mix them before broadcasting. However, avoid mixing urea with SSP (single super phosphate) in the same application if the mixture will sit — it can become lumpy. Always check your crop's recommended NPK ratio first.

The basal dose is the fertilizer applied at or before sowing/planting, worked into the soil. It typically includes the full phosphorus and potassium requirement plus a portion of nitrogen (usually 1/3 to 1/2). The remaining nitrogen is given as top-dressing later — for example, urea at tillering for wheat. Basal application ensures nutrients are available to young roots from day one.

It depends on your soil and crop. DAP (18-46-0) has higher phosphorus concentration (46% P₂O₅), so you need less product per acre — good for transport and handling. SSP (16% P₂O₅) also provides sulphur (~11%) and calcium (~19%), making it better for oilseeds, pulses, and sulphur-deficient soils. DAP is usually cheaper per kg of phosphorus, but SSP adds secondary nutrients. Use our Compare tool to check which is cheaper per kg of P₂O₅ at your local prices.

A soil test measures your soil's existing nitrogen, phosphorus, potassium, pH, and organic matter. Instead of using a blanket recommendation, the fertilizer dose is adjusted — if your soil already has high phosphorus, you apply less P fertilizer. This saves money and prevents over-fertilization. We recommend getting a soil test every 2-3 years through your local agriculture department. Our calculator uses standard recommendations; for soil-test-based precision doses, consult your local soil testing lab with these standard figures as a starting point.

Once applied, urea converts to plant-available ammonium within about 2–4 days through natural soil enzymes, then to nitrate over the following 2–4 weeks depending on soil temperature and moisture. In practical terms, a single urea application feeds the crop for roughly 4–6 weeks, which is why nitrogen is usually split into 2–3 doses across the season. Losses as ammonia gas are highest on hot, dry, alkaline soils when urea sits on the surface — working it into moist soil reduces this.

Urea (46-0-0) supplies only nitrogen at 46% N — the most concentrated nitrogen fertilizer available. DAP (18-46-0) supplies 18% nitrogen plus 46% phosphate (P₂O₅). In practice, DAP is used as a basal dose at sowing when the crop needs phosphorus for root establishment, while urea is used for nitrogen top-dressing during active growth. They serve different primary purposes, which is why farmers often use them together rather than as substitutes for each other.

Start with a soil test if possible — it tells you what your soil already has so you only add what is missing. Then use the Plant Dose Calculator on Fertilizer Dose: enter your plant type and pot or bed size, and it gives the exact grams per plant. As a rule of thumb, apply in small splits rather than all at once, water after granular application, and always follow the label rate — more fertilizer does not mean more growth and can burn roots.

Well-rotted farmyard manure typically contains around 0.5–1.0% nitrogen, 0.2–0.5% phosphate (P₂O₅), and 0.5–1.0% potash (K₂O), but this varies widely with the animal source, feed, bedding material, and how it was stored and composted. Because the nutrient content is low and variable compared to mineral fertilizers, FYM works best as a soil conditioner — it adds organic matter, improves soil structure, and supplies micronutrients — while mineral fertilizers provide the precise NPK dose the crop needs.

Early morning (before about 9–10 am) or late evening are the best times to foliar-feed plants. Leaf pores (stomata) are open, temperatures are cooler, and spray droplets stay wet longer, which improves nutrient absorption. Avoid spraying in the heat of midday — droplets dry too fast for good uptake and concentrated residue can scorch leaves. Also skip spraying just before expected rain, which washes the feed off.

The three numbers on a fertilizer bag (for example 15-15-15) are the percentage by weight of nitrogen (N), phosphate (P₂O₅), and potash (K₂O). So a 50 kg bag of 15-15-15 contains 7.5 kg each of N, P₂O₅, and K₂O. Note that phosphorus and potassium are expressed in their oxide forms by industry convention, not as elemental P and K — the Fertilizer Dose calculators handle this conversion for you.

Ammonium sulphate (21-0-0 plus 24% sulphur) supplies nitrogen together with sulphur, making it useful where soils are sulphur-deficient — common in high-yielding cereals and oilseeds. It has an acidifying effect on soil, so it suits neutral to alkaline soils well, but use it cautiously on already-acidic soils. It is also a good choice when you want nitrogen without adding any phosphorus or potassium.

No — foliar feeding is a supplement, not a replacement. Leaves absorb nutrients quickly but in small amounts, making foliar sprays ideal for correcting micronutrient deficiencies (zinc, iron, boron) or giving a quick boost during critical growth stages. But the bulk of NPK must come through the soil because plants need kilograms of nutrients per acre, and leaves simply cannot absorb that volume. Use foliar feeding alongside your soil-applied basal and top-dressing program, not instead of it.

The standard formula is: fertilizer needed (kg) = (nutrient needed in kg × 100) ÷ nutrient % in the fertilizer. For example, if wheat needs 50 kg of nitrogen per acre and you are using urea (46% N): 50 × 100 ÷ 46 = 109 kg of urea per acre. For phosphorus from DAP (46% P₂O₅): if you need 30 kg P₂O₅, you need 30 × 100 ÷ 46 = 65 kg of DAP. Our Dose Calculator does this automatically for your crop and area.

No — 19-19-19 is a synthetic (chemical) fertilizer. It is manufactured to contain exactly 19% nitrogen, 19% phosphate (P₂O₅), and 19% potash (K₂O) in every granule. Organic fertilizers like FYM, compost, or vermicompost have much lower and variable nutrient content (typically under 2% NPK combined). If you want organic certification, 19-19-19 does not qualify. It is, however, a convenient balanced option for general plant feeding where organic status does not matter.

Dhaincha (Sesbania aculeata/bispinosa) is a fast-growing legume grown as green manure, mainly in rice-wheat systems. Sown before paddy transplanting, it grows 6-8 feet in 45-60 days, then is ploughed into the soil where it decomposes and adds 60-80 kg of nitrogen per hectare — roughly equivalent to 130-175 kg of urea. It also adds organic matter and improves soil structure. Seed rate is typically 20-25 kg per acre, and it needs no fertilizer itself since it fixes atmospheric nitrogen.

In Pakistan and India, the standard fertilizer bag weighs 50 kg. This applies to urea, DAP, MOP, SSP, and most granular fertilizers. Some specialty products (micronutrients, water-soluble fertilizers) come in smaller packs of 1, 5, or 25 kg. When calculating doses, always convert your per-acre requirement into number of bags: for example, 109 kg of urea per acre = just over 2 bags (2.18 bags).