Late perennial ryegrass - diploid

  • Glenarm is a late diploid perennial ryegrass which was bred in Northern Ireland by AFBI and first officially listed in 2015
  • Performs very well under both cutting and grazing management schemes although it’s performance is best suited to silage management
  • Glenarm’s key feature is an excellent first cut yield of 109% of control

Species: Lolium Perenne

Officially listed in: England and Wales

Heading dates: England & Wales 2nd June

Ploidy: Diploid

Bred in: Northern Ireland

Most suited to: Any medium - long term grazing and / or cutting ley



Across the multiple geographical location, and throughout the year, Glenarm provides high quality forage from both silage and grazing management. Grazing D values are particularly good and the high early spring growth displayed by Glenarm requires cutting at the correct growth stage to ensure quality is maximised for 1st cuts.


Other Attributes

Glenarm has excellent Crown Rust resistance (7.4) and a Mildew resistance of 8.1. It has excellent winter hardiness and good ground cover.

Being a diploid, you should expect an average of 600,000 seeds per kilogram and a slightly more prostrate growth habit. Glenarm therefore brings ground cover and a higher plant population than tetraploid counterparts to mixtures.


Before recommendation, Glenarm has been extensively trialled across almost 10 location in the United Kingdom to gather data on its performance in multiple climatic conditions.

Glenarm was bred for Barenbrug UK at the AFBI (Agri-Food and Biosciences Institute). The variety was named after a village on the North Antrim coast.



DESCRIPTION: Dark green, densely or loosely tufted. Folded shoot and leaves.

FLOWERING HEAD: Flattened spike with the spikelets arranged alternately on opposite sides of the stem. The spikelets are stalkless with the narrow, rounded face fitting against the stem.

LEAF BLADE: Ribbed on upper surface, smooth and shiny underside. Red at base of stem.

AURICLES & LIGULE: Auricles are usually well developed, up to 1/12 of an inch (2 mm) long, or are sometimes lacking.

Late perennial ryegrass