In agroecosystems, small increase in biodiversity can lead to large benefits for ecosystem function. Cover crop mixtures can increase the functional trait diversity of crop rotations during windows between cultivation of primary crops. To date, much of the empirical research on biodiversity and ecosystem function has focused on single functions, but there is growing interest in understanding the relationship between diversity and multifunctionality. This study integrates functional ecology and ecological nutrient management frameworks to assess how soil fertility status affects ecosystem functions from cover crop mixtures across working farms.