The practice of incorporating diverse cover crops, multispecies swards, or companion cropping is rooted in the idea of mimicking the natural diversity observed in nature.
In environments where multiple plant species co-exist, they each play unique roles in capturing energy and unlocking nutrients. These plant relationships not only have the potential to boost yields but also to contribute to the overall health of the soil.
Farmers have recognised the significance of diverse planting practices for thousands of years. Even without the scientific understanding of nitrogen fixation that we have today, dating as far back as 37 BC, the ancient Roman scholar Varro observed the soil-enriching benefits of growing legumes.
Similarly, indigenous peoples in North America have a rich history of companion cropping, exemplified by the “Three Sisters” planting technique.
In this planting triad, squash, maize and beans form a symbiotic relationship: beans fix nitrogen for maize, maize stalks offer climbing support for beans, and squash plants provide ground cover, retaining moisture and suppressing weed growth.
Despite this enduring relationship with diverse cropping, modern farming has moved away from this practice. However, escalating fertiliser costs, coupled with declining soil health and a growing awareness of environmental issues, are compelling farmers to reassess the benefits of introducing species diversity back into their farming practices.
For livestock farmers, this shift involves a resurgence of multispecies swards, while arable farmers are embracing diverse cover crops, crop rotations, and companion planting.
Footprint Farmer says diversity is key
An avant garde farmer in this movement is Footprint Farmer and “Phillip Reck Soil Farmer of the Year 2023” Gareth Culligan.
Gareth has successfully used direct drilling, cover cropping and companion cropping to profitably farm 600 acres of arable farmland in Co Louth for more than two decades.
On a recent visit to his farm, Gareth explained that including a wide variety of plants and, importantly, plants from different plant families, into his cover crop mixes and rotations has been key to his success.
His resulting diverse mixes have proven instrumental in enhancing soil health and reducing pest and disease pressure for his cash crops.
Here, he shares the simple table he uses to determine the components of his cover crop mixes.ADVERTISEMENT
Over the coming months, we’ll be taking a deeper dive into Gareth’s vast experience and knowledge on soil health and showcasing how, by mimicking nature, he has found a way to reduce his input and labour costs and increase the long-term health of his soil, while still running a profitable farm business.
Learn more: BASE Ireland
BASE Ireland (baseireland.ie) is a farmer-led organisation dedicated to knowledge sharing among Irish farmers, with the overarching goal of building soil health to increase long-term profitability and sustainability.
Most knowledge-sharing happens through farm walks organised on members’ farms, which bring a wealth of valuable information shared by farmers, who are actively using these techniques on their farms.
A long-term member, Gareth says that BASE is a supportive network, welcoming to new members, and that existing members are always keen to share their experiences, ideas and information.
Members of BASE are committed to integrating the following practices into their management regimes to boost soil health:ADVERTISEMENT
If you are interested in joining BASE Ireland, please email email@example.com
Determining components of cover crop mixes
Gareth uses the simple table below as a tool to determine the components of his cover crop mixes. Through experience, he has discovered that the key to success is including a wide variety of plants from different plant families. The resulting diverse mixes have proven instrumental in enhancing his soil health and reducing pest and disease pressure in his cash crops.