The benefits of applying lime to Irish soils are well known. It’s a vital component for improving soil fertility, increasing nutrient use efficiency, and reducing the requirements for chemical fertilisers.

Indeed, the last number of years have seen a large increase in the use of lime by Irish farmers with approximately 1.3 million tonnes spread in 2021 and a similar figure likely for 2022.

With the new €16/t National Liming Programme lime subsidy announced, and the closing date of April 20, just around the corner, Eoin O'Carroll, the chairman of the Ground Limestone Producers Association of Ireland (GLPAI) and a Grolime member, discusses the key aspects of the programme and some essential top tips when liming this year.

The GLPAI manages the voluntary certified trademark ‘Grolime’ under which companies that meet necessary criteria are authorised to promote and sell their ground limestone.

All Grolime companies undergo independent twice-yearly testing for Total Neutralising Value (TNV), Moisture Value and Grading, in line with the national specification for ground limestone.

“The €16/t lime subsidy is a very welcome incentive and will provide great opportunities for farms that are currently below optimum soil fertility levels," Eoin said.

“For example, current national soil tests from Teagasc indicate that 47% of dairy farm soils, 57% of drystock farm soils and 39% of tillage soils require lime to neutralise high soil acidity levels.

“The benefit of regular lime application for cereal farmers is a multiple of the cost, with research showing that applying €100 worth of lime to tillage soils results in €600-700 of extra production,” Eoin added.

The payment will only be made on valid claims relating to a minimum of 10t of ground limestone and a maximum of 200t. Farmers must not exceed a maximum application rate is 7.5t/ha.

Eoin explained: “Lime application is possible all year round, however there are specific times of the year where liming is more beneficial.

"For example, once fields have been grazed off, it is an ideal time to apply lime. In addition, when fields are being closed for silage harvesting, it is advisable to begin planning for lime application following the first cut of silage.

"It is also recommended to apply lime following the second cut of silage to help build grass covers for the final grazing rotation of the year.”

When reseeding, lime should be applied at time of reseeding and incorporated into the seedbed to result in increased seed germination and establishment.

Although farmers who are participating in the programme must have up-to-date soil tests (maximum of four years old from date of purchasing the lime), a soil test is not required to apply for the programme; this can be done afterwards.

“Soil testing is the best indicator of how much lime is needed to reach the target soil pH. The best time of the year to take soil samples generally tends to be from September to March,” Eoin said.  

“Raising the soil pH will increase the supply of nitrogen (N) from organic matter by up to 65 kg/ha/year. At current fertiliser prices, this offers a cost saving of €160/ha on the annual fertiliser bill,” Eoin said.

The importance of a good-quality lime product cannot be underestimated. To qualify for the National Liming Programme, lime can only be purchased directly from quarries licenced by the Department of Agriculture, Food and the Marine (DAFM) to manufacture and market liming materials.

All Grolime-certified suppliers are licenced by the DAFM to manufacture and sell ground limestone for use as a soil conditioner in Ireland.

Minimum standards for ground limestone include:

All lime sold in Ireland must have a TNV greater than 90% to conform to the DAFM's specification;
At least 35% of ground limestone (350kg/t) should have a particle size <0.15mm. This component of the lime is fast acting and very reactive and will start working immediately (0-6 months);
The remaining 65% lime (650kg/t) will be broken down in the soil in the medium term (6-24 months) and helps to maintain soil pH levels in the longer term until the soils are re-sampled in year four.

Applicants must complete an application form on www.agfood.ie by the closing date of April 20, 2023.  

Grolime suppliers are acutely aware of the expectations and needs of farmers and are available to assist them with any questions they may have on the National Liming Programme. To find your local Grolime supplier, click here.