Soils at optimum levels of fertility have declined in Ireland. According to Teagasc, the number of soils at optimum levels for soil pH, phosphorus (P) and potassium (K) has decreased by 3%, down to 16%.

Soil is described as being at optimum fertility when it is at a pH of 6.5 and the P and K indices are at index 3.

As fertiliser use declines amid high prices, this trend in decline is likely to continue.

Fertiliser sales figures from the Department of Agriculture showed a decline in overall sales of nitrogen, P and K in the 2021/2022 season.

However, sales of P and K were reported to be down 26% and 24% respectively for the same time of year.

Essential nutrients

P and K are essential crop nutrients and while costs may be high, it is important that farmers do not neglect P and K in their soil. Building soil indices is extremely difficult and costly when soils are at low levels.

Ensuring soil pH is at the optimum level can help to make nutrients in the soil more available as your soil works more effectively and you may even see an increase in your P and K levels in your soil tests when pH is improved.

Start to plan now for lime application in the spring time. Look at your soil tests and see what fields need lime and which ones should be prioritised.

Nationally, Teagasc reported that the percentage of soil samples with a pH greater than 6.2 declined by 8% to 54%.

The percentage of soils at index 1 and 3 for P increased to 54%, while the number of soils at index 3 and 4 for P decreased to 46%. Soil K levels remained steady, with a slight decrease in the number of soils at index 4.