It really depends on the condition of the soil. If it's compacted or full of large lumps of clay then do it, otherwise just spread the organic matter on top, cover it and let nature do its thing.
Ok I'll not bother in that case. It's a bit uneven from potato rows but not compacted There's clay about 10" down, I'll just flatten a bit and pile on top.
It really depends on the condition of the soil. If it's compacted or full of large lumps of clay then do it, otherwise just spread the organic matter on top, cover it and let nature do its thing.