Manure and Compost Nutrient Value in Ontario
Manure is fertilizer. These are the plant-available nutrient values OMAFRA publishes for common Ontario organic amendments — the portion the crop can actually use in the year of application.
Plant-available nutrients, as applied
Values are kilograms of available nutrient per tonne of material as applied. Prices are editable estimates for budgeting, not quotes.
| Source | N (kg/t) | Pâ‚‚Oâ‚… (kg/t) | Kâ‚‚O (kg/t) | Typical cost | Notes |
|---|---|---|---|---|---|
| Cured compost | 1 | 2.4 | 4.9 | $55/t | ~46% dry matter. Slow-release, builds soil organic matter. |
| Solid cattle manure (FYM) | 2.5 | 3 | 7 | $30/t | Dairy/beef avg, bedded. Excellent K source. |
| Poultry (layer) manure | 11 | 9 | 10 | $90/t | High analysis — apply by N to avoid P buildup. |
| Sheep / goat manure | 2.8 | 3.2 | 8 | $40/t | Well-balanced, good for forages & horticulture. |
Timing and incorporation change what you get
- Incorporate within 24 hours. Surface-applied manure loses ammonium nitrogen to volatilisation fast — losses of half the available N are realistic on a warm, windy day.
- Spring beats fall for nitrogen. Fall-applied manure N is exposed to a full winter of leaching and denitrification before the crop needs it.
- Phosphate and potash are stable. Timing matters far less for P and K than for N.
- Do not apply to frozen or snow-covered ground. Runoff risk is high and it is restricted under Ontario's nutrient management rules.
Biological inputs
| Input | What it contributes |
|---|---|
| Rhizobium inoculant (legumes) | Supplies the soybean/pulse N requirement biologically — no fertilizer N needed. |
| Pivot Bio PROVEN (corn) | Field-average ~25–35 lb N/ac (≈28–39 kg N/ha). Subtract from the N plan as a credit. |
| Phosphate-solubilizing bacteria (PSB) | Improves uptake of soil & applied P. Est. 20–40 kg P₂O₅/ha equivalent. |
| Mycorrhizal inoculant (AGTIV / MycoApply) | Expands root reach for P & water; supports lower starter-P rates. |
Crediting manure against your fertilizer bill
Work out the crop's total requirement first, then subtract what the manure delivers, then buy fertilizer for the gap. Our calculator does this automatically — pick the organic pathway, choose your source, and it shows delivered versus required for every nutrient.
Related guides
Build your own nutrient plan
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