Meeting EFA Requirements with Autumn Sown Green Covers
Sowing a cover crop post-harvest is undertaken by听relatively few听growers听at present.听Generally,听it听is used to provide听additional听autumn/winter forage for livestock听(e.g.听stubble turnips),听or as a method to improve soil structure and fertility.听听
This autumn, however, an increase in the number of growers sowing green cover crops is expected. Firstly, this is due to more livestock farmers requiring Ecological Focus Areas (EFAs) under Enhanced Greening following the removal of the 75% grassland exemption. Secondly, beneficial changes have been made to EFA green cover guidance, introduced this year. These include:听
- An increase听in听the number of species that can听now听be included in听cover听crop mix. New additions:听alsike听clover, crimson clover,听persian听clover, buckwheat, kale, stubble turnip, forage rape, winter beans.听
- The听removal of听the restriction on grazing before 31 December.听
The requirement听continues to be听to听establish听a green cover consisting of two or more of the following crops as the predominant听crops:听The full听list,听in alphabetical order,听is:听
There are limits to the amount of biomass and听benefit听an autumn sown听cover听can听achieve.听Earliness of听sowing is key,听especially if there are small seeds in your chosen mixture. Ideally听sow听by the end of August. If you are later than the first week in听September,听ensure your predominant species听is a large听seed which has the supply of energy to get the plant听well established.听听
Soil moisture is another limiting听factor.听The early harvest in 2025听provided an ideal opportunity for establishment; however, for some growers, dry ground and a lack of rainfall meant this opportunity did not听materialise.听
Available soil nitrogen is another potentially听limiting factor. If the land听is听under听continuous arable cropping with no additions听of听organic听manures,听then the听nitrogen available to boost growth will be low. Applying 30kg听nitrogen will make a significant difference to the听potential听biomass,听however听if you are in听a听Nitrate Vulnerable Zone听(NVZ)听this听needs to be applied in August.听Weather conditions will dictate whether N applications are听viable听in late听summer and听autumn, preparation听of听an听nutrient management plan can help with ensuring seeds go into the best fertility giving the crop the greatest chance of fast establishment.听
The question听of听what to听sow depends听on the听benefits you are trying听to achieve.听If听non-EFA听for听livestock,听then stubble turnips and听westerwolds听are听a听good听fast growing听option. After the stubble turnips听are grazed,听and in good ground听conditions听the grass will continue to regrow right through to the spring as it is frost hardy.听This provides valuable protection for the soil over winter and mops up any nitrogen but can also be a听bonus听early bite of grass in the spring.听If听it鈥檚听for EFA,听then replace the听westerwolds听with听a听cereal听or vigorous听growing听black听oat. If you are grazing with听sheep,听it鈥檚听worth听noting听sheep听will听preferentially graze barley and rye before听oats.听The inclusion of clover should only be done if early sown and only sow听annual or red clover听rather than white clover.听Annual species听such as crimson clover听is听a common听choice but听also consider听balansa听which听is more vigorous and less susceptible to frost.听If you are considering including听vetch,听make sure it is听hairy听vetch听as it is much more frost resistant.听
Be aware of unintended consequences.听Mustard听establishes听quickly,听but it will听also multiply clubroot levels in your soil,听so leave out if you have winter听brassicas such听oilseed rape听or swedes听in your rotation.听Buckwheat is included in the list and grows well in spring summer sown mixtures,听but it听contains听photosensitive听compounds so do not include if听you plan to graze with stock. Other health conditions relate to the fact that the biomass.听A听highly fermentable low听dry matter听material听which can give rise to听twisted gut.听Lambs should be introduced gradually and be double or triple vaccinated against Pasteurella and clostridial diseases. Brassicas also present risks of nitrite poisoning,听haemolytic听anaemia听(SMCO), and goitrogens leading to iodine deficiency.听Having a grass runback听which allows a gradual introduction to the cover is a useful grazing management tool.听
If sowing for soil health听benefits,听then the inclusion of multiple species is the goal听(three听or more, ideally听five)听to exploit the synergies that can arise with听the听soil microflora.听Different听plant species听also听provide听a range听of root architecture. For example,听many plants root to 10cm,听but phacelia, radish,听linseed,听vetch听and buckwheat will听reach 20cm in the autumn and 30cm when sown in the spring or summer.听If your intention is to听benefit听soil听mycorrhiza听fungus听then听don鈥檛听sow听a brassica听because they听cannot听associate with听brassicas.听
Finally, keep an eye on the costs. You听have seed,听cultivation听and possible听fertiliser听costs听to consider.听Seed costs听can quickly听increase听above 拢100/ha听when going听for a听multispecies听mixture. Make sure the听species in the mix are听appropriate for听Scottish听growing听conditions听and do not die with the first听touch of frost听and be prepared to听adjust your mix听if听sowing is delayed into September.听
Five Top Tips听
- Refer to the updated 2026 guidance for EFA options which can be found听on the听
- Green听cover EFA option requires you to听establish听a听green cover consisting of two or more crops as the predominant听crops.听听
- Consider听crop听options carefully. Be aware of limiting factors such as soil moisture and nitrogen.听
- Ensure that the听mix听is听appropriate for听frost.听
- For advice and help with听green听cover crops,听get in touch with听your local consultant.听听
Useful Links听
Donald Dunbar,听Principal Consultant,听Donald.Dunbar@sac.co.uk
Posted by SAC Consulting on 16/02/2026
