SFI Companion Cropping (CIPM3)

This content was published in good faith on 10th November 2024. While we strive to keep our information accurate and current, agricultural practices and recommendations may evolve. For the latest guidance and advice tailored to your specific needs, please contact your local Agrii representative.

Companion cropping constitutes an important action under the Integrated Pest Management section of the Sustainable Farming Incentive (SFI) scheme.

Action CIPM3 pays farmers and growers £55 per hectare per year for companion cropping on arable or horticultural land in an effort to control weeds and pests without the use of chemicals.

But what exactly is companion cropping and what do you need to do to access the funding? In this article, we find out.

What is companion cropping?

In its most basic form, companion cropping is the practice to growing two crops at the same time – generally a cash crop and the companion crop – to drive one or several benefits.

This approach is particularly useful for arable farmers wanting to improve soil quality and reduce the amount of herbicides, pesticides, and fertiliser they use.

The definition can also include intercropping, where the two crops grown together are both main crops. Legumes and cereals are often grown in this way as they have complimentary root structures and growing patterns, and both can be harvested for either human or livestock consumption.

Undersowing is another way to propagate a companion crop and involves herbal or clover leys sown into a stubbles to create a ‘living mulch’ into which the cash crop is drilled.

What are the benefits of companion cropping?

To be featured in the SFI scheme, the various actions have to benefit the environment and CIPM3 is no different.

Companion cropping has the potential to deliver a range of benefits for farmers, soil health, and the wider environment, including:

• Disease control. Including a companion crop can slow or even halt the spread of disease through the main cash crop.
• Soil health. Companion crop root systems and plant residues add organic matter to the soil as they decompose which improves soil structure, water retention, and increases soil microbial activity. The presence of companion crops also reduces soil erosion.
• Managing pests. There are two main ways in which companion crops can be used to manage pests. One is to use them to attract the natural enemies of the pests that attack your cash crop. The other is to select a companion crop the pests prefer over your cash crop to keep them at bay.
• Weed control. Companion crops can play a beneficial role in controlling weeds by reducing the space available for them to grow, shading them out, and by competing for nutrients in the soil.
• Input costs. A major benefit of companion cropping for both the environment and farmers is the reduction in crop inputs, including fertilisers, pesticides and herbicides, through nitrogen fixing and cycling in the soil and more natural disease, pest and weed control.

But before we look at the specific actions outlined in the SFI scheme, we need a definition of what improved grassland actually is under the government scheme.

Most people know it as grassland that is activity managed for livestock grazing or the production of forage, with fewer varieties of plant than more natural, unimproved grassland.

But is there more to it than that?  

Certainly, for the purposes of SFI, there is.  

According to the government, to qualify as improved grassland the sward composition must include at least two of the following:  

• More than 30% cover of rye-grass and white clover 
• No more than eight species per m2, including grasses 
• Less than 10% cover of wildflowers and sedges, excluding white clover, creeping buttercup, docks, thistles and ragwort 

As well as the sward composition, the government’s definition of improved grassland also extends to how it is managed. To qualify, management of the land is likely to include:  

• Regular re-seeding, or within the last 15 years 
• Regular fertilising with typically at least 100kg per hectare of nitrogen as compound fertiliser or animal manures and slurries 
• Boom spraying herbicides to treat weeds 
• Active, well-maintained field drains 
• Taking any conserved forage as silage at least once a year 

Grassland defined as improved encompasses a wide range of farm and land types, including organic systems.  

As well as improved grassland, there is a classification of pasture which is considered semi-improved. Semi-improved grassland is grassland that has been modified in some way through agricultural interventions such as fertilising, drainage or grazing, but still has a greater diversity of species compared to improved grassland.  

Like improved grassland, semi-improved grassland is consider eligible land under the SFI scheme.

To qualify, the grassland must have been managed in certain ways, including: 

• Not reseeding for at least 15 years 
• Applying low or no artificial fertiliser or animal manures and slurries 
• Applying localised or no herbicide to treat weeds 
• Leaving field drains unmaintained or maintaining them infrequently 
• Taking conserved forage as hay or haylage no more than once a year 

Common companion crops

There are many different plant varieties that can be used in companion crop but there are also a number of tried and tested combinations. Some of the most popular include:

Beans and wheat

As mentioned earlier, legumes and cereal crops go together like ham and eggs so it is no surprised wheat sown with a companion crop of beans is a popular choice. This is an example of intercropping as both plant varieties can be harvested as a cash crop.

The combination has a number advantages. Firstly, as legumes, the beans fix atmospheric nitrogen rather than take it from the soil, as the wheat does. So, the two plants don’t compete for this vital nutrient. The wheat can also utilise any legume residues from previous cover or companion crops that is present in the soil.

The beans act to help reduce the pest burden on the wheat by providing habitat and food for favourable insects.

Growing the two crops together also helps reduce weeds by reducing the space in which they have to grow, and outcompeting them for nutrients.

However, sowing wheat and beans together can be a challenge as it requires a special kind of drill that can cope with two different seed sizes and depths.

One way around this is to sow wheat into bean stubbles and let the volunteer bean plants act as the companion crop.

Beans and oats

Winter beans and oats are another popular intercrop combination where both plants contribute significantly to the overall success of each crop. Beans fix nitrogen from the air and in the soil, reducing the need for inorganic fertiliser, and the oats reduce weed populations. They do this by sucking up nitrogen in the local area, driving yield while at the same time depriving weeds from absorbing it.

Another advantage of beans is they continue to grow when soil temperatures drop, unlike some other popular companion crops such as linseed.

As with wheat, oats can be sown into bean stubbles so the volunteer beans can act as the companion crop.

Cereals and linseed

Linseed is another potentially effective companion crop to sow with cereals. It is easier to sow than beans as it can be mixed in with the cereal seeds in a single hopper. Like beans, linseed is not impacted by most pre-emergence herbicides, making it a great choice for cereals crops.

Linseed doesn’t compete with the main crop above ground and below ground it has deep, vertical roots that condition the soil without competing with the main crop for nutrients. Linseed also has reduced nitrogen demands compared to wheat or barley, so doesn’t poach nitrogen from them.

On paper, linseed could make a good companion crop for winter barley. However, winter barley is extremely competitive which can mean establishing any companion crop alongside it is a challenge.

Buckwheat and OSR

Buckwheat can be a particularly effective companion crop for OSR for a number of reasons. Firstly, it is fast growing and develops a thick canopy, making it difficult for cabbage stem flea beetles to get to the OSR when emerging.

It also attracts predatory insects that will eat flea beetle eggs, larvae, and adults, significantly reducing the incidence of these pests.

Buckwheat also provides nutritional benefits to the OSR. It is known for scavenging phosphate which is releases back into the soil after being killed off, and once killed, it breaks down in the soil quickly to improve soil organic matter and soil health, and make other nutrients available to the main crop.

OSR also works well with berseem clover and fenugreek as the deep root growth of these plants enhances soil structure and aids the OSR to establish more robustly. The ability of these crops to trap nutrients can be highly beneficial in the long term, too.

Peas and oats

Peas and oats are often grown together to produce forage for beef and dairy producers. As legumes, the presence of the peas increases the protein content of the end forage, as well as digestibility. As a nitrogen fixer, the peas also improve soil nitrogen levels and cycling.

A pea and oat mix can also make an effective nurse crop useful for suppressing weeds when establishing perennial plants.

Herbals leys

Undersowing cash crops with herbal leys is another excellent way to access CIPM3, as this provides a ‘living mulch’ into which to sow the cash crop. Undersowing with mix including clover will also increase the amount of nitrogen available to the main crop, and this can be very effective with maize.

Herbal leys can be kept in place after harvesting the main crop to decrease soil erosion and increase soil health.

As stated, there are a number of SFI actions in the 2023 scheme that can be carried out on improved grassland that aim to improve food provision and habitat for farmland wildlife, and soil health. These include:

• IGL1 – take improved grassland field corners or blocks out of management
• IGL2 – winter bird food on grassland fields
• IGL3 – 4m to 12m buffer strip on improved grassland
• NUM2 – legumes on improved grassland

Under the 2024 updated SFI scheme, actions that can be implemented on improved grassland include:

• CIGL1 – take improved grassland field corners or blocks out of management
• CIGL2 – winter bird food on grassland fields
• CIGL3 – 4m to 12m buffer strip on improved grassland
• BFS3 – buffer in-field ponds on improved grassland
• CNUM2 – legumes on improved grassland

CIPM3 – companion cropping and SFI

As we mentioned earlier, the SFI scheme makes provision for companion cropping under action CIPM3 listed in the Integrated Pest Management (IPM) section.

According to DEFRA, the objections of CIPM3 are to:

• Support an IPM approach by acting as a trap crop for pests or by supressing weeds
• Provide a habitat for birds and invertebrates, including pollinators and natural crop pest predators
• Manage nutrient efficiency
• Protect soil and improve its condition.

The action can be carried out on arable land below the moorland line, which includes arable land used to grow crops, temporary grassland, arable land lying fallow, and permanent crops on horticultural land.

Extra consent must be obtained before carrying out CIPM3 on an SSSI or land with historic and archaeological features, however. The action pays £55 per hectare per year for a duration of three years. It can be a rotational action, meaning it be can carried out at different locations on your farm for each of the three years, or it can be static, meaning it is carried out in the same location each year.

To be eligible for the funding, the companion crop does not have to be present for the full growing period of the main crop, but it must be managed in such a way that it can reasonably be expected to achieve the action’s aim and its intended purpose.

You can establish the companion crop by:

• Trap cropping – sowing a trap crop to attract pests away from the main arable or horticultural crop
• Inter-cropping – sowing the companion crop with the main arable or horticultural crop
• Undersowing – sowing a companion crop to form a living mulch beneath the arable or horticultural crop.

You can use an existing companion crop to get paid for this action if it meets this action’s requirements. 

As with all SFI actions, you must keep evidence to show what you’ve done to complete CIPM3 which could include field operations at a land parcel level and associated invoices, photographs, and other documentation. 

To read more about the Sustainable Farming Incentive, visit our SFI hub.