The recommendations in this section are using the RoI fertiliser classification system and are based on Teagasc research. Due to slight differences between the RoI and NI classification systems, these recommendations are only a guide for Northern Ireland farmers. They can be converted between the RoI and NI classification systems using this CONVERSION TABLE
Units/acre |
| Table
30. |
| Index |
N |
P |
K |
| 1 |
180 |
30 |
53 |
| 2 |
145 |
24 |
28 |
| 3 |
130 |
16 |
20 |
| 4 |
115 |
0 |
0 |
|
|
| Table
31. Application rate (bags/acre) |
| Index |
K1 |
K2 |
K3 |
K4 |
| P1 |
3 x 10:10:20 |
1 x 0:7:30
+
3 x 24:7.5:0 |
1 x
0:10:20
+
3 x 24:7.5:0 |
2 x 16% P |
| P2 |
2.5 x
0:10:20 |
1.5 x
10:10:20
+
0.5 x 16% P |
1 x
10:10:20
+
1 x 16% P |
1.50 x 16% P |
| P3 |
4 x
18:4:12
or
2 x 0:7:30 |
1.5 x 10:10:20 |
1 x
10:10:20
+
0.5 x 16% P |
1 x 16% P |
| P4 |
1 x 50% K |
0.75 x 50% K |
0.4 x 50% K |
0 |
|
|
| -
- - - - - - - - - - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - - - - - - - |
| Fertiliser
Recommendation |
Autumn application of some nitrogen
may be necessary, for local knowledge of the area consult your advisor. Some of the P K recommendations have to be applied in the Spring in some cases. In late February, top dress with 35% of the Nitrogen application and the remainder in early April.
Boron should be applied to O.S.R. as a routine measure on low Boron soils, high PH soils, and light sandy soils. Sulphur should be applied to O.S.R. on light , free draining soils. It can be applied in the top dressing with Sulfa CAN, A.S.N. or Ammonium Sulphate (20 units S/acre). |
 |
Example
1 |
A farmer is in a low fertility area (P1,K1).
The fertiliser regime will be 3 bags of
10:10:20. |
|
Example
2 |
A farmer is in a medium fertility area (P2,K2).
The fertiliser regime will be 1.5 bags of
10:10:20 + 0.5 bags of
16% P. |
|
Example
3 |
A farmer is in a good fertility area (P3,K3).
The fertiliser regime will be
1
bag of 10:10:20 + 0.5 bags of 16% P. |
|
|
|
