Winter Composting Tips
At this latitude there probably aren’t too many people actively winter composting, unless you have an indoor space for thermophilic piles (and are hardcore!). Most folks tend to have a static pile out the back, where yard waste is thrown during the warmer months and kitchen scraps tossed year-round. Small worm farms are also becoming more common.
In both scenarios we rely on worms to do the turning for us. Keeping everything aerobic as they chow down on their diet of microbes and poop out more diversity than went in, they ensure the end product will be suitable for plants. It takes them around 12 months to aerate and consume pathogens in a pile.
To check if moisture in your pile is optimal for composting worms, grab a handful and give it a good squeeze – if 3 drops come out, you are in the right range. Worms also need protection from freezing (think large thermal mass).
Beneficial microbes prefer 1 drop on the squeeze test. If waterlogging occurs – more than 4 drops or a steady steam – the stage is set for anaerobic (potentially pathogenic) organisms to flourish. If ice forms in a wet pile, many cell walls will pop and microbial diversity will drop.
Winter tips for happy worms and microbes:
- If your pile isn’t under cover, protect it from heavy rain and snow with tented tarps, to direct water down and sideways. Leave air space between the tarp/s and the top and sides of the pile for the microbes to breathe and to buffer against freezing.
- Positioning on pallets avoids waterlogging where your pile meets the soggy ground.
- Encourage fungi and prevent a stinky mess by adding an equal or higher amount of “brown” materials (dead leaves, paper or wood materials) each time you add in “greens” (kitchen waste).
- Move portable worm farms indoors. For an outdoor “worm farm” that withstands freezing temperatures and results in a beautiful highly fungal inoculum, consider building a Johnson-Su bioreactor.
What on earth is a Johnson-Su bioreactor?! Check out the Winter/Spring CVRD recreation guide to join me for a deep dive into the soil food web, thermophilic composting and the Johnson-Su method. Workshops held Wednesday evenings, March 27th -April 10th. Details at www.springhillsoil-lab.ca.
