Dear Reader-

Here at PlantCatalyst® we’re passionate about agriculture and we love to read articles about a variety of agricultural practices, issues and trends.  To that end we’ve begun asking writers to submit blogs that our followers might find interesting.  For those of us in the northern hemisphere winter is quickly approaching and gardening season is largely over.  We’re now focused on how best to ensure a good crop next year and we hope this blog will help!  The blog was written by Ashley Winfrey, a Missouri based agriculture teacher, and it’s called “Composting in Cold Weather.”  We hope you enjoy it!

Composting in Cold Weather

If you thought your garden chores were at a virtual standstill with winter approaching, you’ll want to read on because there are a few important tasks that you can complete to help nourish your garden even in the cold weather months.

Composting is a simple way to add nutrient-rich humus to your garden to encourage more plant growth, restore essential resources to depleted soil, and recycle those unwanted kitchen scraps and lawn clippings. The best part, however, is that it is free and easy! Composting allows you to take everyday waste and turn it in to “black gold” for your gardens and flower beds.

If you have already formed a compost pile or bin, you may be concerned with cooler weather approaching. No worries! Composting in the winter months can still be a very productive venture. A few extra precautions can be taken to ensure that your compost pile remains functional and productive.

The most important factor in your compost pile is also the most susceptible to cooler weather: your microbes. As temperature drops, microbes’ metabolism slows down. As a gardener, you have three responsibilities when it comes to composting:

  1. Help microbes maintain a high metabolism
  2. Provide the ideal habitat for microbes to feast
  3. Provide healthy nutrient-rich humus for your spring gardening needs

How do you effectively accomplish these things?

Similar to all other living organisms, microbes need a well-balanced diet. All compost piles require a high-quality mixture of carbon and nitrogen, also referred to as “browns” and “greens”. An ideal compost pile would be 1/3 green materials (nitrogen-rich) to 2/3 brown material (carbon-rich). Carbon provides an energy source for microbes, similar to carbohydrates for humans. Meanwhile, nitrogen allows microbes to build cell structure. A lack of either material could provide a shortage for microbes, resulting in inefficiency and slow productivity.

Green composting materials includes items such as grass clippings, coffee grounds, manures, and food scraps (from non-meat and non-dairy sources). Meat and dairy products attract rodents and begin to generate unpleasant odors. Citrus fruits should also be avoided when composting because many worms and microbes will not eat them (causing longer decomposition time) and they form mold easily.

Brown composting materials that are ideal for providing carbon include dead leaves, straw, non-treated sawdust, wood chips, small braches and twigs, and shredded cardboard. Newspaper and other non-glossy papers may be used as well. Glossy or foil paper are often high in dye and ink content and are treated with other paper chemicals. This causes them to be unsuitable for microbes.

Particle size of the organic matter is another important factor to consider when adding it to the compost pile. When temperatures drop, microbes (similar to humans) can become sluggish or lethargic. By shredding organic materials into smaller pieces, the pile heat up or decomposes uniformly, and the small particles form a better “mat” to provide insulation and hold in heat that radiates from the compost pile’s core. This protects the microbes and pile from the colder temperatures externally and the weather conditions.

Depending on your weather zone, humidity and winter winds may largely affect the amount of moisture that is available within compost piles. The ideal moisture content for a compost pile should range from 40-60 percent. This is a requirement because microbes need moisture to survive. They have to stay hydrated and if the moisture content of the pile falls below 40 percent, microbes can become dormant or inactive due to dehydration. During the winter months, watering a compost pile may cause temperature to drop or ice to form. However, to assist the microbes in maintaining productive compost piles, moisture-deficient piles should be watered at warmer times within the winter months.

Typically, in summer months, to increase composting rates, piles are turned every three to seven days and bins are turned every three to four days. However, in winter months, you should avoid turning a compost pile to help ensure an insulative layer is on the exterior. Extra insulation precautions may also be taken to ensure your microbes have the ideal environment for turning waste into nutrient-rich garden humus.

Placement of compost piles can help provide essential factors. In the winter, placement of compost piles or bins in areas with full sun can help provide sun-exposure for assistance in temperature regulation. However, some piles may need other physical insulation precautions, such as straw bales, tarps, and trenches.