I've used "clear" plastic before, and have seen white tarps/plastic used. I think it is important that there is some sunlight reaching the plant, but I can't say for sure. Plants that get buried in snow and/or leaves seem to do fine for other people, so maybe it doesn't matter.

I have used clear plastic tarps as well as just whole leaf bags or other light blocking materials to cover over the bamboo and I don't think it matters especially when temperatures stay below 40F on a regular basis.

It seems like the most important thing is to have a solid tarp and not something like burlap which still exposes the bamboo to cold winds. A solid tarp also traps heat to the ground so the bamboo doesn't get exposed to temperatures nearly as cold as in the air especially with another layer of snow on top.

Most temperate bamboos are pretty hardy so you might not need tarping at all, or maybe only on the coldest months in January and February.

I use white greenhouse overwintering film, Provides 55% light transmission.

Here is a video on covering bamboo. You only need to cover it the first winter.

Jim

Here is a link that might be useful: Overwintering Bamboo

awesome! thanks guys. ill def put this info to use.

If you only have one plant that you want to get bigger for next year, a home-made greenhouse or poly-tunnel might be useful in extending the growing season on both sides as long as you stick some barrels of water and perhaps a strong metal halide light to supplement the 8 hours of weak winter sunlight.That might provide some marginal gains, but tarping by late December should be enough to keep them green by next spring.

I have many plantings already so I don't really protect those, but my potted ones all go into one of the ebay 12X7X7 greenhouses and the ones I can't fit will go into a bed surrounded by leaf bags and likely double tarped with lots of leaves around them to guarantee nice plants by next year. I probably won't do this until the weather threatens to get below 20F.

Here's a link that shows around how much protection I give my groves. It's only around 3 inches of leaves/ mulch/ sawdust, or any dried garden scraps which provide a barrier between the roots and a potential deep freeze.

Here is a link that might be useful: Picture with 7 of my plantings

I've been trying different tarps in the past few winters and for bamboos, something as simple as a trash bag is enough to protect most temperate bamboos, including moso which is marginal here over winter completely. Even a few layers of painter's plastic will work so I don't think people need to waste hundreds of dollars on commercial tarps. Bamboos are generally dormant when the soil temperature is below 40F, and I've covered them with black trash bags, and they came back green after the winter so I doubt they need light either. The trick is to completely block the wind, and hold the plants down to the ground so they can be insulated by the warmer soil temperature, which is even better when theres a couple feet of snow over the tarp.

For corm plants like gunneras and bananas, I've found that filled leaf bags are surprisingly effective in winter protection. All I need to do is put some heavy branches or bricks on top of them to make sure they don't blow away when there are 70mph winds which actually happened this spring.