While it is true that the legumes you planted do "fix" nitrogen from the air and deposit it in nodules in their roots, this nitrogen is not available for the vegetables you planted. It would not be available until the plant's roots begin to break down, so right now, all they are doing is getting in your way. Generally, when we plant a cover crop, if it is planted during the growing season, we consider it a "green manure." That is, after it is as tall as it's going to get, but before the seeds are viable, we till it under or remove it and compost it. That way, it provides organic matter and a bit of nitrogen. We suggest you follow the suggestions given to you by the soil testing lab for nitrogen fertilizer. Remove the legumes and compost them. Don't give up on cover crops, though, because they are a great way of improving your garden soil.

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