In this blog post, Yunhui Liu and team share insights from their recent global meta-analysis on how cover crop mixtures can enhance agricultural sustainability by promoting multiple ecosystem functions.
As agriculture faces growing challenges from climate change and land degradation, cover crops are increasingly recognized as an essential tool for improving soil health and farm resilience. While the use of single-species cover crops is well established, multi-species cover crop mixtures are gaining attention for their potential to deliver a broader range of ecosystem benefits. To explore this potential, Yunhui Liu and team synthesized 1,895 paired data points from 61 field studies across the globe to compare the performance of multi-species mixtures versus single cover crops across a wide range of agroecosystems.
Mixing matters: More biomass, more nutrients, better yields
The study found that multi-species cover crop mixtures outperformed single species in several key areas. On average, mixtures increased cover crop biomass by 21.7% and accumulated more carbon (+27.7%), nitrogen (+27.7%), phosphorus (+22.8%), and potassium (+24.1%). These gains translated into a 4.9% boost in the yields of the following main crops—an effect especially pronounced in paddy fields and with certain species combinations such as milk vetch-rapeseed and milk vetch-ryegrass.
Improving soils above and below ground
The benefits of cover crop mixtures extended below ground as well. Mixtures enhanced soil moisture by 1.5%, increased total soil nitrogen by 5.8%, and boosted microbial biomass carbon and nitrogen by nearly 38%. Notably, they also improved fungal richness (Chao1 index +12.6%) and reduced soil bulk density and electrical conductivity—key indicators of soil compaction and salinity, respectively.
Tailoring mixtures to maximize impact
Not all mixtures performed equally. The analysis highlighted that both field type and species combination played a critical role. Paddy systems, in particular, saw the most significant improvements across ecosystem functions. Among mixtures, milk vetch–rapeseed and milk vetch–ryegrass stood out for consistently delivering high biomass, nutrient accumulation, and subsequent crop yields.
Concluding remarks
The findings suggest that multi-species cover crop mixtures are a promising practice for boosting both productivity and sustainability in farming systems. But for maximum benefits, mixtures should be carefully designed to suit local conditions and management goals. Functional complementarity—pairing species that bring different strengths—is key to optimizing results.
Read the full article “Cover crop mixtures enhance multiple ecosystem functions: A global meta-analysis” in Journal of Applied Ecology.
