Worm composting is a fun and easy way to recycle fruit and vegetable waste. Also known as vermicomposting, this process results in dark rich crumbly compost that will benefit the garden.
It is easy to get started. You first need a container with a lid to keep things dark, moist and pest-free. You can buy a ready-made worm bin, or make one yourself (see sidebar).
Before you start, determine the size of container that is ideal for your household. For a couple of weeks, weigh your kitchen scraps. Allow one square foot of surface area in your bin for each pound of weekly kitchen waste. For example, if you produce 6 pounds of kitchen waste each week, you might use a bin that is 3 feet long by 2 feet wide, and 12-14 inches deep. You will need 2 pounds of worms for each pound of kitchen waste. Or start with just a few worms and wait for the population to grow.
Now add bedding material to your worm bin. Bedding holds moisture and provides a place to bury kitchen waste. Bedding materials should be light and fluffy to allow air circulation. Bedding material should not be toxic to worms, because they will, in time, consume the bedding as well as the food scraps.
Shredded newspaper makes ideal bedding. Leaves, shredded computer paper, coconut fiber (coir), wood chips or any combination of these are also good. All of the bedding material should be soaked in water and wrung out.
After placing bedding material in the bin, you are ready to add red worms (Eisenia fetida).
Spread the worms over the top of the bedding. After a few minutes, the worms will travel down into the bedding to avoid light. Once the worms are within the bedding, you are ready to add kitchen waste.
Worms like all fruit and vegetable scraps, including peels, chopped into about 1-inch pieces; crushed egg shells; coffee grounds along with the paper filters; tea bags with the staples removed; bread, and cereal. Do not feed the worms any meat, fish, dairy products or oil.
Bury food scraps into the bedding, taking care to cover them. Keep the bedding material moist. To avoid overfeeding, add food scraps after the worms have processed most of the scraps in the bin.
Add more bedding as needed to maintain space to bury the food. When the bedding starts to look like dark, rich humus in two to six months, it is time to harvest the compost.
Spread a tarp on the ground in the sun and empty your worm bin in a pile on the tarp. Worms will travel down into the pile to avoid light. Scrape off the top layer of compost, set
it aside, and wait a few minutes. Then repeat the process. When mostly worms are left, put them back in your bin, add new bedding material, and start again.
The compost you harvest can be used to amend your garden soil, or to top dress potted plants.
Judy Mann is a certified WSU Clallam County Master Gardener.
Build a worm bin
Here is an easy way to make your own worm bin. You will need a sealable plastic or wooden container that is 12-14 inches deep. An approximately 10-gallon plastic storage box is ideal.
Drill holes in the bottom of the container for drainage using a one quarter-inch drill bit. Drill holes in the lid and sides of the container for air circulation using a 1/16 inch bit. Space the holes about an inch or an inch and a half apart.
The ideal temperature range for your worms is 50-80 degrees Fahrenheit. Avoid freezing temperatures that may kill the worms. Keep your bin in a garage or basement during winter, and a shady area outside the remainder of the year.
‘Novel Small Fruits for the Home Garden’
Make sure to join us for the upcoming Digging Deeper presentation “Novel Small Fruits for the Home Garden,” by local gardeners Cyndi Ross and Marty Kaler, from 10:30 a.m.-noon on Saturday, Aug. 6, at the Woodcock Demonstration Garden, 2711 Woodcock Road. Kaler and Ross will talk about less commonly grown small fruits that do well in our climate including red, white and black currants, aronia berries and honeyberries. Master Gardeners will also be hosting a Plant Clinic during the event. Come with your questions and hopefully leave with some answers. Presentations and workshops cover basic gardening topics relevant to most home gardeners. Seminars are free, but donations to help support the WSU Clallam County Extension Master Gardener program or Master Gardener Foundation of Clallam County are appreciated. Visit extension.wsu.edu/clallam/master-gardener-calendar.