You have touched on mustard as a green manure. Are there others and which best for a veg garden in your opinion?
I am attending a gardening course and part of it is to identify various garden plants (flowers shrubs trees etc) Please recommend a good easy laymans guide for this. I like the Royal Horticulture New Encyclopedia of Plants and Flowers, but it is very expensive. I also like the RHS Encyclopedia of Gardening, but likewise too expensive.