Should I cut my rhubarb plant down before winter?

Springtime

the leaves will be killed by the frost and will die down and dry out. they can be removed in the spring if anything is still left.

Thanks, I wanted to know this also.

To extend the season, cut off the flower stalks. ... Rhubarb doesn't like the heat and won't do much during the summer, but you may get some more stalks in the cool fall season. At this time of year, be sure to leave 2/3 of the stalks on the plant so it can store enough energy to survive the winter.

After it has finished fruiting, twist any remaining stalks off and pull out any limp leaves. Then leave to hibernate over the winter. Rhubarb can grow naturally even far up north in Canada past latitude 55 so you do not need to cover it. It should grow up again from the roots in the spring.