Turn livestock manure into a precise fertilizer. This chart gives average N-P-K values by animal, how much nitrogen is actually available each year, how much to apply for a target nitrogen rate, and the safety rules for using manure on food crops.
1. Average Manure N-P-K by Animal Type (Fresh Weight %)
| Manure Type | N (%) | P₂O₅ (%) | K₂O (%) | N-P-K Ratio | Organic Matter (%) | N Level |
|---|---|---|---|---|---|---|
| 🐔 Chicken | 1.5 | 1.0 | 0.8 | 1.5-1.0-0.8 | 40 | Very High |
| 🐇 Rabbit | 1.5 | 0.5 | 1.0 | 1.5-0.5-1.0 | 45 | Very High |
| 🐑 Sheep / Goat | 0.7 | 0.3 | 0.9 | 0.7-0.3-0.9 | 50 | Medium |
| 🐎 Horse | 0.7 | 0.3 | 0.6 | 0.7-0.3-0.6 | 55 | Medium |
| 🐄 Cow / Dairy | 0.6 | 0.3 | 0.5 | 0.6-0.3-0.5 | 45 | Low–Medium |
| 🐖 Pig / Hog | 0.6 | 0.4 | 0.4 | 0.6-0.4-0.4 | 35 | Low–Medium |
Values are averages for fresh manure. Actual content varies with animal diet, bedding material (straw, shavings), moisture, and how the manure is stored. Composting concentrates nutrients (removes water) but also loses some nitrogen to the air.
2. Nutrient Availability Over Time
| Nutrient | Year 1 | Year 2 | Year 3 | Notes |
|---|---|---|---|---|
| Nitrogen (N) | 50% | 25% | 10% | Only half is available immediately; rest is slow-release organic N |
| Phosphorus (P₂O₅) | 80–90% | ~10% | — | Most P is available the first year; it binds to soil over time |
| Potassium (K₂O) | 80–90% | ~10% | — | Highly available; leaches more readily than P |
Why this matters: If you apply manure every year, nitrogen accumulates. Account for residual N from previous years' applications to avoid over-fertilizing, which wastes money, burns plants, and pollutes waterways.
3. Manure Needed for 2 lbs N per 1,000 sq ft (Year 1 Available)
| Manure Type | Total N % | Available N % (×0.50) | Manure Needed (lbs) | Equivalent (5-gal buckets) |
|---|---|---|---|---|
| Chicken | 1.5% | 0.75% | 267 lbs | ~9–10 buckets |
| Rabbit | 1.5% | 0.75% | 267 lbs | ~9–10 buckets |
| Sheep / Goat | 0.7% | 0.35% | 571 lbs | ~18–20 buckets |
| Horse | 0.7% | 0.35% | 571 lbs | ~18–20 buckets |
| Cow / Dairy | 0.6% | 0.30% | 667 lbs | ~20–25 buckets |
| Pig / Hog | 0.6% | 0.30% | 667 lbs | ~20–25 buckets |
Formula: Manure Needed = (Target N × Area ÷ 1,000) ÷ (N% × 0.50 ÷ 100). Most vegetables need 1–3 lbs of available N per 1,000 sq ft per season. Bucket weights vary by moisture — 25–40 lbs per 5-gallon bucket is typical.
4. Nutrients in 100 lbs of Each Manure Type
| Manure | Total N (lbs) | Available N Year 1 (lbs) | P₂O₅ (lbs) | K₂O (lbs) | Organic Matter (lbs) |
|---|---|---|---|---|---|
| Chicken | 1.5 | 0.75 | 1.0 | 0.8 | 40 |
| Rabbit | 1.5 | 0.75 | 0.5 | 1.0 | 45 |
| Sheep / Goat | 0.7 | 0.35 | 0.3 | 0.9 | 50 |
| Horse | 0.7 | 0.35 | 0.3 | 0.6 | 55 |
| Cow / Dairy | 0.6 | 0.30 | 0.3 | 0.5 | 45 |
| Pig / Hog | 0.6 | 0.30 | 0.4 | 0.4 | 35 |
5. Manure Safety Rules for Food Crops
⚠️ Raw Manure & Pathogens
Fresh manure may contain E. coli, Salmonella, and other pathogens. Never apply raw manure to crops that will be eaten raw within the waiting periods below. Composting to 131°F (55°C) for 3 consecutive days kills most pathogens.
| Crop Type | Minimum Wait (Raw Manure) | Composted Manure |
|---|---|---|
| Crops touching soil (lettuce, strawberries) | 90 days | 0 days (safe anytime) |
| Root crops (carrots, potatoes) | 120 days | 0 days (safe anytime) |
| Above-ground fruiting (tomatoes, corn) | 90 days | 0 days (safe anytime) |
| Crops that touch soil & are eaten raw | 120 days | 0 days (safe anytime) |
6. Best Uses by Manure Type
🐔 Chicken Manure
Highest N — great for heavy feeders (corn, tomatoes, squash). Must be composted or aged; fresh chicken manure burns plants. Compost first to reduce pathogens.
🐇 Rabbit Manure
"Cold" manure — safe to apply fresh directly to the garden. High N, won't burn. Pellet form makes it easy to side-dress plants. Excellent for raised beds.
🐑 Sheep / Goat Manure
Also a "cold" manure — safe fresh. Pelletized, easy to spread. Good balanced N-P-K. Excellent for vegetable gardens and can be applied any time.
🐎 Horse Manure
Often has lots of bedding (straw/shavings) which is high carbon. Compost well to avoid nitrogen tie-up. Great for building soil organic matter.
🐄 Cow Manure
Lower N, high organic matter. Mild and safe when composted. Great for conditioning soil and top-dressing. Less risk of burning than chicken manure.
🐖 Pig Manure
Similar to cow in N but higher P. Must be composted — pig manure can carry parasites. Good for fields and compost piles, less ideal for direct garden use.
7. Application Tips
🔬 Test Your Soil
Test N-P-K and pH before applying manure. Over-application of phosphorus (common with manure) can lock up micronutrients and pollute streams.
📅 Apply in Fall or Early Spring
Incorporate manure into the soil before planting. Fall applications give organic matter time to break down and nutrients to stabilize.
🌿 Compost First When Possible
Composting kills pathogens, reduces volume, stabilizes N, and eliminates the "burn" risk. Aged (6+ months) manure is the next best thing.
💧 Water It In
Always water manure into the soil to prevent nutrient runoff, volatilization (N loss as ammonia), and attraction of pests.
♻️ Account for Residual N
25% of last year's N and 10% from 2 years ago is available this year. Reduce fresh applications accordingly to avoid over-fertilizing.
🚫 Avoid Runoff
Don't apply manure before heavy rain. Keep it out of waterways and wells. Buffer strips of grass along streams help filter runoff.