sbl

There are several "tricks" I thought I would mention that can help with cold protection. Insulation of course is one of the first things we can do, but trapping the "heat" is another. There are several things we can do--adding any form of thermal mass is helpful--rocks, bricks, bags of dirt will help, but buckets of water is even better. When water freezes, it has to release heat to the surrounding air--over 80 calories per gram.

Adding any heat source will also help--anything like a heat tape, Christmas tree lights, or a plain light bulb (just make sure it can't start a fire).

Natural sources of heat in the form of radiation comes from the ground or any nearby walls--when possible, include as much of this heat source as possible underneath your cover. In other words, do not just put a sheet over the top and pull it tight around the trunk if you could have spread it out over the ground and weighted it down with bricks.

Spraying water on a tree is another method of cold protection, but contrary to what some people think, it is not the insulation factor, it is the freezing process--if you stop adding water, the protection will stop. So you can't just get a coat of ice on the tree and turn the water off--you have to keep it going as long as it is freezing.