For beekeepers who live in northern climates with winter months that sometimes reach single digit temperatures, wrapping your hives will often lower hive loss. This practice of wrapping hives is not a guarantee for winter survival, but coupled with other winter preparation this will improve your odds.
First of all, I don’t recommend wrapping your hives if you live in a warmer climate. Hives can easily handle night-time lows in the twenties. The other issue to be aware of is humidity and proper ventilation. If you live in a humid climate and don’t have good air circulation in the hive, you run the risk of water condensation dripping back down on the bees.
The three main items in winter preparation is adequate food storage, low varroa mite levels and disease prevention. If these three things are not taken care of, then wrapping your hives will do little to prevent the death of your hives.
I usually wrap my hives in late November and unwrap them at the end of January just before I send them to California for the almond pollination. During this two month time period from late November to late January I usually have a ten to fifteen percent hive loss. My best year, I only had a seven percent loss. Before I started wrapping my hives, I often experienced losses that exceeded twenty percent. Even though the improvement is only five to ten percent when wrapping your hives, I feel it is worth the effort.
There are many ways and materials to use when wrapping your hives for winter. As I explain below how I do it, this may not work for your situation. Some of the reasons it works well for me is that I have a hive entrance in each deep which helps with air flow into the hive. Second, humidity levels are low in Utah where I live. I don’t have problems with water condensation inside the hive.
Steps to Wrapping Hives
First, I group my hives together on six pallets (twelve hives per side) and install a top layer of four-inch insulation. Some beekeepers use straw as insulation.
Second, I wrap a sheet of plastic visqueen over the top and ends to keep the insulation dry and to act as a wind barrier down the ends of the row. Beekeepers in humid climates prefer wrapping with breathable tar paper.
Third, secure the viqueen with wood lath and nails.