In zone 6 and cooler, a good way to help protect plants over winter is to add leaves so I ended up collecting over 100 bags to get the job done. This helps protect shoot buds and rhizomes that are close to the surface since it provides extra insulation, and also allows snow to cling to it. I believe this helps to reduce the chance that the plant dessicates over winter when it gets extremely cold and the moisture is sucked out of the plant. Tarping is the next step, but that can happen in late December when the temperatures can drop below 0F, and I will likely do it to the marginally hardy species.
Phyllostachys propinqua beijing
Phyllostachys edulis moso seedling with fargesia denudata on left, fargesia murielae on right
Phyllostachys aureosulcata spectabilis
Moso bicolor before adding leaf mulch