Eco-friendly practice does not have to stop when the thermostat drops
Composting, cost-effective and environmentally friendly manure management, involves the biological decomposition of manure and bedding by a host of microorganisms. For these bacteria, fungi, and other microbes to do their job effectively, they require the right environment, not too hot or too cold, nor too wet or too dry. Food must also be available in the right form.
The winter months present a variety of challenges providing the ideal environment for the microbes to do their work, including colder temperatures, snow, winter winds, and lower humidity. Some tips to help you manage your winter compost pile include:
Make your pile larger – In general, compost piles should be at least one cubic meter in size (3.5 ft x 3.5 ft x 3.5 ft). During the winter months, consider increasing the size of your pile. This will provide greater insulation around the pile’s core, keeping it at the right temperature for the microbes to function. The exterior of the pile will likely be too cold to compost, but hey, some compost is better than no compost. The colder your winter climate, the larger you should consider making your pile.
Keep the snow out – A cover over your compost pile is essential to keep the snow and rain out. Otherwise, it will turn into a wet mess. If your compost system already has a roof, consider adding a tarp directly over the compost pile for extra insulation. While too much snow mixed in the pile should be avoided, savvy winter composters have successfully used snow packed over a tarp as extra insulation.
Put your old hay bales to good use – Just as too much moisture is a bad thing, so too is too little water. The combination of lower humidity in winter and cold winds can easily dry a pile below the ideal 50% moisture content. Got extra hay bales lying around? Stack them up around the compost pile to make a temporary wind break. You can also cover the pile with hay to serve as extra insulation.
Turn the pile less frequently – Microbes must work extra hard to get the temperature of the compost pile up to 135-150ºF, the ideal temperature to kill weed seeds and parasites (Caution: don’t go above 160ºF, or you’ll kill the microbes, too). Don’t make it harder on them by turning the pile prematurely and exposing the warm core to the cold winter air. Use a composting thermometer to know when it’s the right time to turn the pile.
Add bulkier bedding to the mix – The downside to turning your pile less frequently is that microbes use up oxygen as they work, and manually turning the pile is a great way to provide fresh air. To reduce the need to turn the pile, consider adding some bulky bedding to the mix to create space for air pockets to reside. Forced aeration composting systems, in which air is mechanically blown into the pile, can also help.
Change your ratio – There’s another benefit to adding more bedding to the pile in winter. Microbes use carbon and nitrogen from the manure and bedding as food, but they need the right ratio. Typically this is around 30:1 (carbon to nitrogen), or around a one to one mix of manure to bedding by volume, depending on bedding type. During winter, your compost can benefit from slightly more carbon, so feel free to add a little more bedding to the mix.
Time – Regardless of how well you manage your compost pile, the process is going to take longer in winter, often around three to five months versus one to three months in summer. Keep this in mind when designing your composting system. Size bins to account for the longer composting times in winter.
Also, remember that finished compost should not be applied to pastures in winter when grasses are dormant. Therefore, even cured (i.e. finished) compost will need additional storage space in winter.
For more help on composting, talk with your local soil and water or agricultural extension agent. They can often provide excellent help tailored to your specific geographical location.
Clay Nelson is the principal of Sustainable Stables LLC, where he provides consulting on horse farm planning, design, and management. Learn more at www.SustainableStables.com .