- £20 / acre. But it " feels " like the right thing to do. I sow cover crops, therefore I is a proper farmer. It allows me to be an arrogant tosspot like the no- tillers on here. + You are subconsciously encouraged to tick the " I've sown or intend to sow cover crops " box on the RPA form. Yields no better, prices no better. Last year for subs in Wales in 2021 I think, so after that won't bother.