Green manure and carrots

I have just dug up my potatoes in the bed where next season I will be planting carrots. I don’t really want it to be left bare over winter so was thinking of sowing some green manure.
Has anyone got any suggestions as to what type taking into account that I would be growing carrots and parsnips next year

I would not dig in green manure before carrots as it may interfere with growing straight roots. Grow another crop as suggested. An alternative is to grow green manure, such as mustard, phacelia, tares and then pull or cut the crop and add it to the compost heap.