How one farmer increased productivity from low-fertility soils

Farming in Portlaoise, Co. Laois, Paul Delaney – a beef and tillage farmer – rented 12.5ha of land in 2015. This land had low soil fertility levels.

The land was low (index one and two) in phosphorus (P) and potassium (K). Just one soil sample required lime. Paul outlined his story at the recent Fertilizer Association of Ireland spring scientific meeting.

The parcel was in old permanent pasture and Paul decided that he needed to address soil fertility before spending up to €300/ac on reseeding.

Nutrient management planning

In autumn 2016,  lime was applied – where the acidity needed to be adjusted – at a rate of 2t/ac.

A nutrient management plan is prepared for the whole farm at the beginning of each season. Every year, Paul applies half a bag of urea to his whole farm in early spring.

In 2016, he decided to apply 18:6:12+S in five splits across the grazing season to the low-fertility soils. The entire P and K allowance was applied to the low-fertility soils in 2017, while only 60% of the N allowance was spread.

Paul’s 2017 fertiliser plan for the low-fertility farm is outlined below. Fertiliser costs came to €225/ha on the 12.5ha of low-fertility soil, while his fertiliser bill on the main farm was €188/ha on index three soils.

Stocking rates

In order to utilise grass as efficiently as possible, Paul divided the land into 14 paddocks (0.87ha each) in 2016. 40 yearling bulls were turned out to grass on March 13, 2017. The total number of animals that grazed the 12.5ha is outlined below.

Paul estimated that 11t/ha of grass dry matter was produced from the 12.5ha over the grazing season. Over 240 days, Paul estimates that the 12.5ha of grass produced 9,000kg of animal live weight.

All livestock were removed from the ground on November 1. 60 round bales of silage were also made from surplus grass.

Savings

Had Paul taken the option of reseeding this old pasture, he would have invested a significant amount on reseeding and the soil would still have low fertility levels.

Paul stated: “I am convinced that, with paddock grazing and appropriate lime and fertiliser applications, even old pastures can make a major contribution to farm output and profitability.”