Teagasc, Ireland's agriculture and food development authority, is advising tillage farmers to make early autumn a priority period for soil testing. After a difficult year in which drought squeezed both grass and cereal crops, it says now is the time to take stock of soil fertility and decide which fields need sampling before 2027.

A soil test gives a field-by-field picture of pH, phosphorus (P) and potassium (K), so that lime and fertiliser go where they are needed and are not spread where they are not. For nutrient-planning purposes results are valid for four years, and farmers should check now for samples that have expired or will need renewing next year; out-of-date results can give a misleading picture and lead to poor decisions.

There is a regulatory reason too. Farms with a grassland stocking rate above 130kg of organic nitrogen per hectare, and land growing cereal crops, cannot apply chemical phosphorus fertiliser without valid soil test results. Farmers in that position should sample the relevant areas now to establish a P allowance for 2027.

Teagasc says soil pH should be the first thing looked at when results come back. Lime improves nutrient availability and helps crops make better use of applied fertiliser: its research shows an average grass response of about 1.5t of dry matter per hectare from lime alone, with an estimated return of €6–€10 for every €1 invested, and an average cereal grain response of at least 1.5t/ha on tillage farms.

With every fertiliser transaction now recorded on the National Fertiliser Database, the authority adds, farmers need to know their allowances and track their use so that limits are not exceeded. An up-to-date test means 2027's lime and fertiliser decisions rest on what each field actually needs, supporting yield while avoiding unnecessary expense. Balanced fertility and pH, it notes, also improve soil health, carbon storage, nitrogen fixation and residue breakdown.

Richard Halleron reported the advice for Agriland.

Source: Agriland