A trial growing a variety of crops to determine the best at building and stabilising soil has found phacelia or oil radish out performed 24 other species.
Funded by Agri-Tech Cornwall the study involved a variety of cover crop including legumes and oats, grown on land provided by Duchy College.
The trial assessed 26 cover crops and varieties on objectives such as biomass production, carbon nitrogen ratio and sequestration, crop height, ground cover and pest damage.
Both phacelia and oil radish produced a lot of biomass, with improvements to nitrogen and carbon sequestration, nutrients in green material and feed for the following crop.
Where a break from brassicas is not needed, oil radish provided the best above ground biomass, improving carbon and nitrogen sequestration.
Vegetable specialist at Elsoms Seeds, and manager of the independently assessed trial, Ian Boase explained: “An incorporated residue from cover crop biomass is a very effective way of getting organic matter back into soils between cultivations.”
Soil organic matter (SOM) is vital for improving soil structure, health and capacity for carbon, nitrogen and water storage.
“With increased industry pressure on sustainable food production and more frequent extremes of weather, growers are seeking more ways to preserve their soils,” Mr Boase added.
Phacelia and oil radish were also less affected by predation from pests. Egyptian clover was the worst affected with 80 per cent damage.