Autumn Reseeding Grassland

Guest article written by Jim Juby of Horizon Seeds.

With the cost of reseeding being £400 - £600 per hectare it is important that it is done correctly and timed to maximise establishment and performance.

Always select the correct ley for your needs looking at available data and performance information. When choosing a ley ensure the supplier names all the varieties in the leys, it allows you to see precisely what you are getting and to evaluate the performance against available data.

Ensuring grass varieties are on the Recommended Grass and Clover Lists in the mix means you have a selection from the best available grasses and the list also provides extensive data on performance.

Why Reseed?

  • Increased yields from existing leys - With constant improvements in grass breeding technology individual varieties are becoming more and more productive, with higher ME and better disease resistance.
  • Increased quality from the ley - ME levels and digestibility will be significantly improved. 
  • Reduction in bought in feed - Feed supplements can be costly, good grass produced on farm is the cheapest form of feed available.
  • Reduction on the Weed Burden - Older leys by nature are weaker growing and often far more open. This allows competitive weed species to establish themselves within the ley requiring more inputs and reduced yield and quality.
  • Improved response to inputs - Denser swards, modern breeding and high vigour of new leys all combine to give a  far better response to any fertiliser applied.

Research has shown that increase in the proportion of the farm reseeded each year increases the amount of grass grown and utilised leading to increased farm net profit. (See table left)



The table below illustrates the increase in input costs per year based on average reduction in perennial ryegrass over a 5 year period (Data collated AHDB research)

*assuming 100MJ per 1kg of gain for 350kg growing cattle

** Based on 3.1p per MJ of ME

Why Reseed in the Autumn?

  • Growing Conditions - In general soil is much warmer which increases the speed of germination and growth, The air is generally cooler than spring and the chance of regular rainfall is much higher, a vital constituent for sustained growth.
  • Less Chemical inputs - Weed pressure is greatly reduced in the autumn which means less competition and better establishment.
  • Spring growth - An established autumn ley will go through the winter in a position to storm away in the spring as soon as the soil is warm enough. This can put your ley 3 - 4 weeks ahead of a spring sown ley and give you a vital boost at turnout or first cut.
  • Ready for summer - If we move into a very dry summer the grass roots are already well established and drought resistance will be much better than that in spring sown leys.
  • Less water management - Spring sowing means you have to worry more about hot weather and the availability of water as seeds need constant supply. Cool autumn rain means less water management will be required.
  • Minimising loss in production - By reseeding in autumn the grass establishes in the run up to winter dormancy and then gets away quicker in the spring. Minimising the amount of time the field is out of production.

If you would like to discuss your seed requirements, please contact Louise Cox on 07943 684215 or e-mail, or David Quance on 07395 498175 or e-mail