The cardboard, platic, and tarps might also choke out other plants. My best results so far are with a thin layer of compostedmanure under 2-3 inches of bark mulch. (The manure replenishes nutrients the rotting wood will consume.)

For #wintermanure, use #compostedmanure (from animals like cows, sheep, or rabbits) or plant #greenmanures like winter #rye, #fieldpeas, or #mustard to improve your #soil. Composted manure can be spread in the late fall to break down over winter, while #greenmanurecrops are sown in the fall.