I have a raised bed that loosely follows a square foot gardening model. This fall is my first time having an actual garden..so I'm a newbie. I have a late summer/early fall crop growing (zone 9) and was wondering what to do after my blue lake bush beans stop producing. I know that the roots have nitrogen fixing bacteria it adds to the soil, and that no nitrogen is needed for them. I read somewhere that cutting them out and then tilling the soil with the roots would be a nitrogen boost to the soil..but would there be a downside to doing that? If I planted a different plant in that space once I tilled it up would I be exposing it to disease or any other problems? Or would it be a good idea to boost give the soil a free nitrogen boost?