AgriLand recently published a reminder on how to calculate seed rate. Knowing the thousand grain weight (TGW) is essential in this process. Farmers should be aware of this figure before ordering their seed, in order to know the correct amount to order.

Teagasc recently published some sample seed rate calculations for 2019 using a range of TGW figures from the Department of Agriculture, Food and the Marine’s (DAFM’s) 2018 trial results for spring barley, wheat and oats.

The range in TGW figures is substantial. For example, TGW in spring barley varieties is ranging between 39 and 54.

Sample spring barley seed rates for 2019

Range in the TGW of spring barley in 2018 DAFM trials (2019 seed):
  • Planet: 47-53;
  • Mickle: 43-50;
  • Irina: 44-54;
  • Gangway: 40-50;
  • Paustian: 42-51;
  • Hacker: 42-48;
  • KWS Cantton;
  • Limona: 44-49;
  • Prospect: 43-49;
  • SY Arderin: 43-52;
  • SY Errigal: 43-51;
  • Wylanda: 39-47;
  • Laureate: 39-50.

Teagasc has compiled a list of seed rates using this range in TGW figures. The time of sowing and percentage establishment were also taken into account.

Data source: Teagasc

Sample spring wheat seed rates for 2019

Range in the TGW of spring wheat in 2018 DAFM trials:
  • Quintus: 37-42;
  • RGT Doubleshot: 35-37;
  • KWS Chilham: 37-41.

Data source: Teagasc

Sample spring oat seed rates for 2019

The same calculations have been carried out for spring wheat and spring oats, as can be seen in the data below.

Range in the TGW of spring oats in 2018 DAFM trials:
  • Barra: 38-35;
  • Husky: 29-35;
  • Delfin: 34-38;
  • WPB Isabel: 32-37.

Data source: Teagasc