The target levels for pH on grassland are 6.2 to 6.3 and P and K should be at index 3.
At these levels, land will be very responsive to applications of lime and compound fertilisers.
On many farms sub-optimal soil fertility will lead to a drop in output and income if allowed to continue.
It is very important to complete a farm fertiliser plan for your farm to avoid further decline in soil fertility levels.
There are five key steps for effective soil fertility management:
The whole farm should be sampled and tested for pH, P and K.
Have one sample for every five to 10 acres.
Take sample in a W shape to get a random sample.
Make sure there is a minimum of 20 cores per sample.
The sample should be taken to a depth of 10cm and during the late autumn to early spring.
Leave at least three months from the last application of fertiliser or slurry
Avoid unusual spots, like where a ditch was removed, feeders, farmyard manure stored.
The cost is small at around €0.50/ac/year
Soil pH and lime
Correct lime status first.
One to two tonnes of lime per acre are removed every five years
Target pH of 6.2 - 6.3 for grassland.
Apply lime as required to increase soil pH up to target, as 60pc of the country has a pH of <6
Apply to bare ground or low grass covers.
Do not apply within six months if on a silage field, as it may affect preservation.
Target P and K Index 3
Aim to have soil test P and K in the target Index 3 in all fields, only 25pc of soils are at index 3
Low index fields will have less productivity and they will require additional fertiliser.
Index 3 soils only require maintenance levels of fertiliser to replace crop off takes.
Slurry and organic manures
Use the resources on your farm.
Most of the value is in the P and K.
Spread slurry and farm- yard manures on low P and K index soils.
Spread as much as possible in the spring to maximise availability of Nitrogen.
Timing doesn't have as big effect on P and K as N
Balance the land with fertiliser
Choose a fertiliser that is well balanced to make up the crop requirements.
The nutrient in the shortest supply will determine the yield
Have N, P, K and S in the correct ratios.
Gordon Peppard is the programme advisor for the Teagasc Green Acres programme email: firstname.lastname@example.org