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Winter Composting and Rock Salt Alternatives

Q:Can I keep adding to my compost pile over the winter? Will food keep biodegrading in the cold?

A: You sure can. Your microbe and spineless soil friends will be a lot slower in colder temps and may even stop in the depths of winter. Most of the time, however, your bin will remain a happy, active little ecosystem of biodegradation. Here are some tips to keep things moving along. Keep adding a handful of leaves on top of each batch of kitchen scraps. If you run out, use sawdust, shredded paper, dryer lint, or clumps of your pet’s recently shed, thick winter coat. The pile does not shrink very quickly in colder temps, which is why it is important to start with plenty of room in the bin before winter starts. The freezing and thawing periods are beneficial. Tough fibers like citrus and banana peels and avocado skins will break down and will be that much easier for the worms to process when things finally warm up again. You can help it along by chopping material into small pieces. For the uber-composter, you can insulate your bin with straw, partially bury it, or move it to a more southern exposure. Anything which conserves heat or adds heat will speed up the action. When everything thaws come spring, your pile might be soggy. Turn it to aerate the material. Add those leaves which somehow sneaked into your garden despite all your raking last autumn, add some soil, then watch your pile shrink again as it turns to rich, black earth. If we get so much snow that you can’t get to your composter in winter, consider indoor worm composting. A pound of red squirmies can consume half a pound of organic waste a day. Rest assured you will not meet red worms cavorting on your countertops on your midnight forays to the refrigerator. They know their place and it’s inside their bin. And harvesting the soil for your indoor plants is a great task for the kids on a stormy winter day. Whichever method you choose, it will ultimately feed your garden rather than the landfill. Q: I’ve been told to buy Calcium Chloride rather than salt to put on my icy sidewalk – is that really better than salt?   A: The official Material Safety Data Sheet (MSDS) says that anhydrous Calcium Chloride (CaCl) is not ecologically reactive and will not biodegrade. This suggests that it won’t hurt your soil or the microbes and plants living in soil the way that salt does. Unfortunately, there does not seem to be enough research done to say whether its buildup over time will affect soil, plants, or the bodies of water that the snow and rain pulls it into through the street drains. I say stick with old fashioned sand or bird seed (thanks Dan for your suggestion a couple of years ago!). Both do the job and have the most minimal impact on your lawn, garden, or the water that drains off into our rivers and lakes.

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