It’s minus 20 degrees outside the kitchen and the garbage bin is full of food waste. Composting the scraps outside would likely lead to icicles.
So what’s the solution, aside from the trash can?
“In winter, vermicomposting is a really good choice for composters in Alaska,” said Lydia Clayton, UAF Cooperative Extension and agriculture and horticulture agent. “Unless you’re really advanced and you really know what you’re doing, the pile will often freeze up.”
Tom Bowser, a Kenai National Wildlife Refuge entomologist, and worm composting gurus Tom Gotcher, of Sterling, and Bruce King, of Soldotna, recently fielded questions about earthworm composting in a Central Peninsula Garden Club meeting.
Worms are a good way to dispose of food waste while producing high-quality compost.
“And that’s terrific to put on your potted plants or whatever you’ve got around,” Gotcher said.
Also, the worms can live in temperatures as low as 38 degrees, he said, though 55 to 77 degrees is the ideal temperature, according to a University of Alaska Fairbanks Cooperative Extension Service pamphlet.
The operation is simple, King said.
“I don’t think it’s rocket science to compost with worms,” he said.
To start, composters need about a pound of Red worms.
Two varieties are acceptable: Lumbricus rubelus and Eisenia foetida, according to the extension service. Other species don’t do as well, Bowser said.
Gotcher said he bought his worms from www.unclejimswormfarm.com.
The worms eat the waste at a two-to-one ration: one pound of worms produces a half pound of worm casings.
Composters then need a container to house their worms. A tote box or any improvised untreated wood or plastic container will work; it just must be shallow, have a lid punched with holes for good ventilation and be chemical-free.
“Literally it’s just a couple stockings of plastic boxes, so there’s nothing fancy about it,” Gotcher said.
There are also commercial options, but they can cost between $80 to $120 from a gardening supply catalogue.
For the average four-person family that produces six pounds of kitchen waste a week, a 6-square-foot box will work well.
Once a box is selected, composters need to layer it with a moist bedding material. Gotcher said he shreds leaves for the material, but shredded paper, manure, peat or soil will also work, according to the extension service.
Bowser said worms need grit to break down their food; composters need to also add sand or topsoil.
The bedding material must not be over-saturated, Gotcher said.
“When it gets wet it makes a thick, hard mat and it doesn’t work too good,” he said. “It needs to be fairly wet. You want it wet enough that when you squeeze it just a little bit of the water comes out.”
The extension service suggests composters saturate 75 to 90 percent of the bedding with water to avoid suffocating the worms. Three pounds of water for one pound of bedding is a good ratio.
Once the worm compost system is completed, composters can begin sprinkling their food waste to the top of the bedding material.
Gotcher said the worms will eat most kitchen waste, but there are some exceptions. Meats should be avoided, he said, because they are too acidic, and composters need to pulverize egg shells before adding them. He said coffee grounds are too course for the worms, also.
King said his worms eat about 1 gallon of food waste a week.
“Worms aren’t the best thing (for large-scale garden composting,) but they’re one of nature’s best,” said Bowser.
Find the UAF Cooperative Extension Service’s publication “Composting with Worms” online at http://www.uaf.edu/ces/pubs/catalog/. Information on the Central Peninsula Garden Club may be found at http://www.cenpengardenclub.org/.
Dan Schwartz can be reached at firstname.lastname@example.org.