Harvests of veg on my allotment going down each year
I went over to no dig quite a long time ago on my allotment. For the past 3 years I have the performance of the plot going down and down. My brassicas don't grow to the size they used to and give small vegetables, beetroot are small, chard and spinach are slower to get going but do eventually perform ok. Beans are ok but don't compare to the gluts I used to get. I used to do well with veg growing for years, but now something is not right. Following Charles Dowding I add a top dressing of fertility every year. On some patches I grow green manure, cut it down when it begins to flower, leave it on the top of the soil and cover with plastic. On other patches I spread well rotted cow manure in small amounts, then cover with plastic. Perhaps I am not adding enough or the right kind of top dressing. Another thought that occurs to me is that maybe I have been adding too much fertility to the soil and this is bringing about chemical changes in the balance of the soil. Any ideas?