How to do the SFI actions for buffer strips
Source: gov.uk (2025-03-27)

Find out how you could do the SFI actions for buffer strips.

It’s up to you how you complete each SFI action, as long as you do it in a way that can reasonably be expected to achieve the action’s aim (which is described in each action).

This voluntary guidance includes advice on how you could establish and maintain a 4m to 12m grass buffer on arable and horticultural land (AHL4) and improved grassland (IGL3).

You may find it helpful to read this guidance, but you do not have to follow it. The requirements you must follow for each SFI action are explained in the ‘Details of the SFI actions’ (https://www.gov.uk/government/collections/sustainable-farming-incentive-guidance#details-of-the-sfi-actions-in-the-sfi-2023-offer-), which you can find in either:
- section 2 of the SFI handbook (https://www.gov.uk/government/publications/sfi-handbook-for-the-sfi-2023-offer)
- the webpage versions of the details of the SFI actions (https://www.gov.uk/government/collections/sustainable-farming-incentive-guidance#details-of-the-sfi-actions-in-the-sfi-2023-offer-)
How to establish and maintain a 4 metre (m) to 12m grass buffer strips (AHL4 and IGL3)

What you’re aiming to achieve

The aim for AHL4 (https://www.gov.uk/guidance/sfi-actions-for-buffer-strips#ahl4-4m-to-12m-grass-buffer-strip-on-arable-and-horticultural-land) and IGL3 (https://www.gov.uk/guidance/sfi-actions-for-buffer-strips#igl3-4m-to-12m-grass-buffer-strip-on-improved-grassland) is that there’s a grass buffer strip with an intact grass sward throughout the year, without tracks, compacted areas or poaching.

Establishing grass buffer strips

You can choose to establish the grass buffer strip by sowing seeds or allowing natural regeneration, unless it will buffer:

historic or archaeological features

water bodies

Where to locate the grass buffer strip

AHL4 and IGL3 explain:
- that you’re required to locate a 4m to 12m wide grass strip so it buffers an existing landscape feature - the strip can be wider than 12m, but you’ll only be paid for the 12m width
- what types of landscape features to buffer
Where to locate the grass buffer strip next to hedgerows

AHL4 and IGL3 explain that the 4m to 12m wide grass strip must be in addition to any regulatory requirements relating to buffer strips and green cover next to landscape features.

If your SFI 2023 agreement started before 31 December 2023, the cross compliance rule (GAEC7a) to have 2m green cover applied. This means the 4m to 12m wide grass strip should already be at least 2m from the centre of any hedgerows, as AHL4 and IGL3 are static actions.

If your SFI 2023 agreement started on 1 January 2024 or later, you may have established the 4m to 12m wide grass strip immediately next to a hedgerow. This is because the cross compliance rules ended on 31 December 2023.

In this case, you’ll need to:

re-establish the 4m to 12m wide grass strip at least 2m from the centre of the hedgerow by the end of the second year of your SFI agreement

maintain the 4m to 12m grass strip at its new location until the end of your SFI agreement

This is because law that came into force on 23 May 2024 (and took practical effect from 1 July 2024) requires you to have 2m buffer strips next to hedgerows. Read the guidance on Hedgerow management rules; buffer strips (https://www.gov.uk/guidance/hedgerow-management-rules-buffer-strips#buffer-strip-rules) to understand how these rules apply to you.

To help you decide where to locate the grass buffer strip, you may find it helpful to do SAM1 (assess soil, produce a soil management plan and test soil organic matter) (https://www.gov.uk/guidance/sfi-actions-for-soils#soil-1).

Sowing a seed mix to establish the grass buffer strip

Sowing a seed mix will establish the grass buffer more quickly, which will reduce the risk of soil erosion.

To prevent damage by soil erosion, you’ll need to sow a seed mix if the grass strip will buffer historic or archaeological features or water bodies.

You can choose a seed mix that contains native grass species. Grass species you could use include: timothy, cocksfoot, crested dog’s tail, red fescue, smooth-stalked meadow grass.

It will help the seeds to germinate if they’re sown into a seedbed that’s:
- firm, consolidated, fine, level and weed free
- moist, which will usually be the case in the autumn – you can sow in the spring, but you may need to increase the sowing rate, depending on weather and soil type
You can broadcast the seeds onto the surface of the seedbed to help germination. Alternatively, you can shallow-drill the seeds up to a depth of 1 centimetre (cm), as small seeds usually struggle to germinate when sown deeper than 1cm.

If the soil is dry enough, rolling after you’ve sown the seeds can improve seed-to-soil contact, retain moisture and reduce the risk of slug damage.

Your seed supplier can:
- help you choose a seed mix that’s the best match for your land and local conditions
- advise you on an overall sowing rate for the seed mix you choose
Establishing grass buffer strips through natural regeneration

Using natural regeneration means the grasses in the buffer strip are local to your area. It will take longer to establish the buffer strip, but it will cost less.

To encourage the seeds that are already in the soil to germinate, you can cultivate the soil between spring and late summer.

Maintaining established grass buffer strips

Once the grass buffer strip is established, AHL4 and IGL3 require you to maintain the grass buffer strip by managing it in a way that can reasonably be expected to achieve the relevant action’s aim (described above).

Cutting AHL4 grass buffer strips

For AHL4, it’s up to you how much of the buffer strip’s width to cut along as much of the strip as possible next to the edge of the cropped area.

Cutting up to half of the strip’s width from the crop edge each year will create a varied grass height and structure.

This will help to provide:
- short grass for birds to forage in, such as grey partridge chicks
- mid-length grass for species like brown hares
- shelter and nesting places for birds and invertebrates in long, rarely cut, tussocky grass
You can only cut the buffer strip in late summer, as explained in AHL4. This is to avoid disturbing breeding birds or damage nests, as birds, nests and eggs are protected by law (https://www.gov.uk/guidance/wild-birds-protection-surveys-and-licences#what-you-must-not-do).

Remove the cut vegetation, where possible, to help reduce the risk of it smothering the flower species and limit weeds. If it’s impractical to do this, you can finely chop them to spread them as thinly as possible.

Cutting or grazing IGL3 grass buffer strips

For IGL3, you can cut (unless it’s for hay or silage) or graze the grass buffer strip with livestock, as long as the action’s requirements are met.

Staggering cutting or grazing, so all the buffer strips are not cut or grazed at the same time, will usually mean there’s always habitat available for invertebrates and small mammals.

Controlling weeds

You may need to control weeds when they appear. To control weeds like docks, nettles, thistles and common ragwort, you can cut the affected area, as long as there’s still an intact grass sward.

AHL4 and IGL3 also allow you to use herbicides to weed wipe or spot treat weeds.