Organic Manure
Organic manure is a valuable source of plant nutrients. The key aim is to maximise the value of slurry, i.e. get the most from its P and K content as well as N. This will be achieved by making sure that it goes to the right place at the right time at the right rate
- P & K – Right Place – Spread on fields/paddocks where fertility is low and where the nutrient demand is highest (e.g. silage field)
- N – Right Time – Spread when potential N losses are low and the potential for uptake by a growing crop is high (February to April)
- Method – Use a Low Emission Slurry Spreader
Plan your slurry application
- Calculate the amount of slurry available
- Assess nutrient value in the slurry (adjust rate accordingly)
- Prioritise silage ground
- Target thicker (higher dry matter) slurry to silage fields
- Direct watery slurry to grazing plots
Slurry application plan
| Plot name or number | Plot size | Crop | P Index | K Index | Feb/March gals/ac, m3/ha | March/April gals/ac, m3/ha |
|---|---|---|---|---|---|---|
| 5 | 9 | Silage & grazing | 3 | 4 | 5.4m3/ha, 3,000gals/ac | |
| 2 | 4.5 | Grazing | 1 | 2 | 2.7m3/ha, 1,500gals/ac | |
Value of slurry (cattle)
| Slurry dry matter % | N Units/1,000gals | P Units/1,000gals | K Units/1,000gals | Value €/1,000 gals |
|---|---|---|---|---|
| 2 - very dilute | 4 | 2 | 13 | 16 |
| 4 - watery | 6 | 3 | 21 | 25 |
| 6 - typical | 9 | 5 | 32 | 39 |
| 7 - thicker | 10 | 6 | 36 | 45 |
Note: On index 1 & 2 soils reduce slurry P availability by 50% and reduce K availability by 10%
Slurry Calibration Tool
Access the Slurry Spreading Calibration Tool here