Surplus grass on farms mean farmers may have an opportunity to reseed, but what’s the latest research from Moorepark saying on selecting grass varieties?

Regular reseeding enables farmers to produce higher yields of better-quality pasture on farms, which boosts feed self-sufficiency and enhances the sustainability of their farms.

When deciding which perennial ryegrass varieties to sow during reseeding, the Pasture Profit Index (PPI) is used as a variety selection tool. The PPI outlines, in economic terms, the agronomic differences between varieties for traits that influence the profitability of ruminant production systems.

Using the PPI

The 2025 PPI list is displayed in Table 1. Performance data for each variety is collected and evaluated through the Department of Agriculture, Food and the Marine’s Recommended List trials, conducted at five locations across Ireland.

Varieties are ranked based on their total PPI value which is calculated by adding its performance in each of the traits that make up the PPI. These sub-indices (and their relative emphasis within the PPI) are spring (19%), summer (6%) and autumn (8%) dry matter (DM) production, mid-season quality (measured as DM digestibility; 25%), silage DM yield (13%) and persistency (29%).

For 2025, Galgorm is the top-ranked variety, with a PPI value of €263 – a €10 increase over the top variety in 2024. The higher the € value for a trait, the greater the variety’s performance.

Cognisance should be taken of a variety’s strengths and weaknesses as indicated by the PPI. The grazing utilisation sub-index does not contain € values but ranks varieties on a scale of one to five stars, with five stars indicating the highest grazing efficiency.

Choosing varieties through the PPI

Using the PPI allows farmers to choose varieties that deliver the best return on investment when reseeding. Focusing on the individual traits helps tailor seed mixtures to suit specific systems.

When choosing varieties for intensively grazed paddocks on the milking platform, those performing strongly in the grazing utilisation, quality and spring/autumn DM subindices should be selected.

Variety selection for paddocks destined for regular intensive silage harvesting would benefit from prioritising the silage and spring yield traits.

Paddocks located on the grazing platform but destined to be closed for silage should aim to combine high silage and utilisation traits.

Research has shown that the performance of a seed mixture can be accurately predicted by averaging the trait values of the individual varieties included in the seed mixture.

Table 1: 2025 Pasture Profit Index

The above was adapted for use on Teagasc Daily from the paper titled: Pasture Profit Index 2025, authored by Tomás Tubritt, Noirín McHugh, Sarah Walsh and Michael O’Donovan.

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