Lime is magic, but are dairy farmers missing a trick by not applying lime this back end?

Co-ordinator of the Teagasc/Tirlán Joint Programme, Seamus Kearney joined Stuart Childs on a recent episode of the Dairy Edge podcast to remind farmers of the benefits of regular lime applications.

“When is the best time to spread lime? Probably today. When was the better time to spread it? Probably yesterday,” Seamus Kearney explained before looking back on historic lime application trends and the possible tax benefits from spreading lime this year.

Irish farmers spread approximately 2 million tonnes of lime per annum back in the 1980s, he explained. Despite a small peak in 2021-2022, national applications are now struggling to broach the one million tonne mark.

“Back in the 1980s, farmers were spreading a load of lime for every 60 dairy cows…it’s the forgotten element,” Seamus Kearney explained.

Nationally, he said, approximately 40% of land under dairy enterprises is lacking lime. Additionally, only ~25% of dairy soils are at optimum levels for lime, phosphorus (P) and potassium (K). Improving the latter (P and K) by first focusing on the former (Lime) will be a necessary step for dairy farmers to produce sufficient pasture quantities in a lower chemical nitrogen environment.

Not only does correcting soil pH from 5.5 to 6.2 release approximately 70kg of N/ha/year of background nitrogen, but it also releases locked P. Additionally, optimising soil fertility for pH, P and K also improves nitrogen use efficiency.

“Lime is magic and by getting lime out you are getting free nitrogen and phosphorus out of the soil. For every euro you spend on lime, you are getting a €7 return on a dairy farm,” Seamus Kearney added.

Huge opportunities exist to correct soil fertility, he explained, before highlighting some of the potential tax savings:

“Dairy farmers are looking at about €400-500 extra output per cow this year between milk being up slightly and milk sales being up by about 8c/L.

“We are going to have a lot more farmers who are not in companies heading into the high rate of tax. From a lime point of view, it is a no brainer,” Seamus added, “For every load spread, you are getting one free from the tax man.”

For full insights, listen to the episode of the Dairy Edge below:

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