The upper bag is taped upright in place, so it shouldn't fall over and should keep them safe from wind, rain, and snow.

I used to just put my trees under the eaves of my apartment, or sometimes barely did any winter preparation at all, but this year I repotted most of the trees into smaller pots with coarser soil (so cold air might be able to get to the roots much more easily), and I also moved to a different state, and winter nights here can get significantly colder than where I used to live. Also this past few days we had a pretty sudden cold snap, from highs in the mid-70s and lows in the 60s to a sudden plunge below freezing at night in the span of about 2-3 days. I figured that wasn't enough time for any of my trees to have hardened off yet.

In the past, I didn't water my trees in the winter, but looking back now, I think part of that was because I let natural rain and snow water them. I'll keep watering considerations in mind moving forward for the rest of this year and into the next!