Hi All,
I wouldn’t disagree with anything anyone has posted on this thread.
My point to John was that I thought it impractical to grow a Green Manure purely to generate material to fill the Compost Bin. I absolutely agree with growing Russian Comfrey for this purpose as it is an extremely effective activator.
As far as Green Manures are concerned I have always believed this to be an excellent way to cover bare soil over winter. Green Manure will help retain nutrients from being leached out by winter rain/snow, will add organic matter to the soil when later dug in, will in some cases, i.e., Legumes, add nutrients from the air and those that root deeply will break up lower levels as well as draw up nutrients from these lower levels.
Charles’s point about nitrogen being used to decompose the dug in material is absolutely correct but once the decomposition has been completed I believe this loss is redressed.
Generally you would dig the Green Manure in about 4 weeks prior to sowing a crop so there is no lack of nitrogen for that following crop.
Don.