This time of year can be puzzling for folks with families learning to garden. With the weather cold, wet and gray again, long periods of time outside seem less enticing. 

Visually, the vegetable garden appears to have less going on. However, this is a great time to begin composting your kitchen waste.

 

Worm bins

There are many methods and devices that you can employ to compost your food waste at home. Popular methods of composting are digestion, burial or tossing your scraps in your curbside collection bin, but for the gardening family, none offers more fun and excitement than a worm bin.

Unlike other food-waste composting methods, worm bins allow decomposition to happen above ground. All the biological processes and fauna of composting can be easily observed in a worm bin, and the vermicompost that a worm bin produces is practically ambrosia for houseplants or seeds in need of a starting medium.

One challenge many families face is ensuring that their worm bin will be able to accommodate all the food waste they generate. This is a great educational opportunity for a mini “waste audit.” 

Collect all organic scraps that your family generates, and separate it from the rest of the waste for one week. Place them into a few quart-sized yogurt containers with lids in the refrigerator marked with a big “X.” Weigh out the collected scraps. 

The golden rule for worm bin processing is 1 pound of food waste per 1 square foot of container per one week. So if your family generates 12 pounds of food waste in a week, you’ll need a bin that has a floor plan of 12 square feet.

There are worm bins available on the market and plans available on-line. 

 

Siting the worm bin

You can construct multiple bins to meet your needs, or put some of your food scraps in your worm bin and the rest in your curbside collection bin. Both approaches are good for the environment. 

To get started, set your worm bin in a site that will neither be too warm or too cold, depending on the season. If you are placing it outside, make sure you can protect it from marauding raccoons, possums and rats, and if you live in bear country, consider an indoor space like a basement or garage for safekeeping. 

Bed the bin with moistened leaves from your garden trees or shredded newspaper (do not use shiny, colored inserts). 

Add red worms (Eisenia foetida) available locally, as well as on-line from Yelm Earthworm and Castings Farm. 

Begin feeding by placing handfuls of food buried into the bedding, in a different spot each time you feed your worms. 

In three to six months, you can begin harvesting once you see all the bedding and food materials have been digested and deposited as beautiful, fine, dark-brown castings by your worms. 

Push all materials to one side of the bin. They will have reduced in volume so there should be plenty of room to do this. 

Re-bed the empty side of the bin, and begin adding food to that side. The worms will migrate over on their own to find their dinner. 

In about a month, you can pull the finished compost from the bin and use it in your garden.

 

Daylighting

Another method that only takes a day is to spread a tarp in the garden and add all the contents of the bin to the top of the tarp. As the light reaches the worms, they will work their way deeper into the compost, and you can harvest from the top of the pile. 

Let it sit an hour, and come back and do it again. 

Eventually, you will be left with the pile of worms in a little bit of compost at the bottom, which can be returned to your freshly bedded bin. 

Worm compost is often called “The Cadillac of Compost.” Try it for yourself and see!

For personalized questions, to find local worm sources and to discuss the best system for your use, call the Garden Hotline at (206) 633-0224. 

Or visit our website for composting brochures, www.gardenhotline.org, and e-mail a question from there.

 

LAURA MATTER is an educator and program coordinator for Seattle Tilth’s Garden Hotline. Graham Golbuff is an educator of resource conservation for Seattle Tilth (seattletilth.org). To comment on this column, write to MPTimes@nwlink.com.