I've always mowed the rhubarb plant in the fall to winterize the plant, but what is the best thing to do to rhubarb if you can't get rhubarb into where it was transplanted to? I have 60 plants in the area (12x50 approx), and picking every stalk in the fall would be a real pain.
I have half a dozen rhubarb 'Timperley Early' at my allotment. I stop picking the stalks in late June/early July then I just ignore them for the rest of the year. In the winter the foliage dies and disappears into the ground. I do try to surround them with a thick layer or well rotted compost in the winter, and in the picking season I will try to water them if they are looking a bit dry. Apart from that I tend to leave them to do their own thing.