Building a Family Worm Bin
Story by Francie Szostak
Photography by Erika Kent
Searching for the perfect family pet?
How about these qualities for your new addition to the family: Only needs to be fed once a week; doesn’t make any noise; has habits that can be used as a teaching tool; and actually creates something beneficial. Sound good? Then it might be time to start a family worm-composting bin!
Worm composting, or vermiculture, is a process that utilizes the digestive power of worms to recycle food scraps and organic material, creating a wonderful soil amendment. Worm castings (or worm poop!) are full of beneficial microbes and are a nutrient-rich, organic fertilizer and soil conditioner. In addition to creating this fertile compost, worms are a wonderful teaching tool for youth and make for manageable pets even for the busiest of families.
Worms as a teaching tool
As kids care for a worm bin they get to experience the cycle of nature in action: Plants growing, dying, decaying and finally returning to the earth to help other things grow. Children can see this system in operation as they watch worms digging, eating food scraps, and creating a rich compost to help a garden grow.
Worms also demonstrate recycling at its finest. In 2011 alone, more than 36 million tons of food waste was generated in the U.S., with only four percent diverted from landfills for composting (source: U.S. Environmental Protection Agency). Children will be delighted to discover that worms enjoy many of the same healthy foods they do as these master recyclers eat the leftovers from their plates and work to minimize your family’s contribution to this food waste.
Creating a Worm Bin
There are many preconstructed worm bins on the market, but creating your own is quite simple and inexpensive.
1. Acquire a worm bin.
The simplest bins can be made from two 10-gallon plastic containers or 5-gallon buckets with holes drilled in the bottom. These are lightweight, portable and cheap.
2. Choose a worm bin spot
Worms are divas and prefer a controlled environment with temperatures between 50-80 degrees. An unheated room like a basement is a great spot. Also, keep worms away from heaters and windows that can cause major temperature fluctuation. If worms get too hot, they will have a worm eruption! (Google “worms escaping bin” to see worms fleeing from the heat of their homes.)
3. Preparing the bin.
Vermiculture systems need drainage holes. Excess moisture can flood out your worms and cause you system to go anaerobic (meaning it is lacking oxygen and rotting). Several holes (⅛ – ¼in wide) should be made with a drill at the bottom of your container, and spaced 3-4 inches apart.
Bins should also be set on a tray or in a second bin to catch excess moisture that run out of the bin. The easiest system is two plastic containers, one main bin with holes at the bottom can sit inside the second, closed-bottom bin.
4. Preparing the bedding.
The foundation material for worm bins is a shredded paper source and soil.
- The paper source can include newspaper, cardboard or paper bags. Glossy paper (magazines) should be avoided.
- Tear paper into ½” to 1” strips.
- Place newspaper strips in a large plastic garbage bag or container. Add water until bedding feels like a damp sponge, moist but not dripping. Add dry strips if it gets too wet.
- Add the strips to the bin; making sure bedding is fluffy (not packed down) to provide air for the worms. Bin should be 3/4 full of wet newspaper strips.
- Sprinkle 2-4 cups of chemical-free soil (either store-bought or from your garden). This introduces beneficial microorganisms. Gritty soil particles also aid the worms’ digestive process.
5. Add worms!
For composting, you want to use red wiggler worms. They multiply quickly and are the worm of choice for veteran composters. Composting worms are sold locally or online (see sources below).
6. Feed Worms!
Worms love to dine on these favorites:
Fruits: apples, bananas, melons and fleshy fruits
Veggies: beans, cabbage, carrots, cucumbers, squash, lettuce, etc.
Grains: oatmeal, pasta, pancakes and non-sugary cereals.
Other: coffee filters with grounds, eggshells, tea bags, and dead flowers
Paper: newspaper, cardboard, dried leaves, cardboard egg cartons
- Break food into smaller pieces. The smaller the pieces, the faster they will break down.
- Bury food scraps under bedding to avoid potential odor or fruit fly problems.
- Worms only need one good feeding per week. One pound of worms contains approximately 1000 worms, which eat about ½ lb. of food per week.
- Monitor the bin every week to see if the worms are eating the food. Adjust feeding levels accordingly. It will take a couple weeks for food to break down completely but you will see changes each week.
- DO NOT FEED WORMS: Citrus fruits, onions, garlic, meat or fish, dairy, greasy chips, candy, pet poop, non-biodegradable items like rubber, plastic and aluminum.
7. Bin Covering
Place a breathable cover over the worm bin. A piece of cardboard, newspaper or even thick burlap, cut to size, works well. This covering will help maintain the moisture balance, keep any possible odors in the bin, and help prevent fruit flies from making a home in the bin. Replace this cover frequently if fruit flies are present, or if bin gets too wet.
Basic Worm Care
Once your worm bin is set up, it needs very simple care. Weekly worm bin tasks can easily be incorporated into a weekly, family chore rotation.
FEED, WATER and FLUFF!
- To keep worms happy, feed them about once a week.
- If bedding dries up, spray with water. (If bedding gets too wet, add dry newspaper strips.)
- Fluff up bedding once a week so the worms get enough air.
- Add more bedding as the worms eat it.
Harvesting Worm Castings
As time passes, you will notice less bedding and more compost in your bin. When your bin is nearly filled with compost, it is time to harvest or remove compost from the bin. The time from starting your bin to harvesting will vary depending on the size of your bin, worm population, and how frequently you add food. Typical time is 2-5 months.
To prepare for harvesting, do not add new food to the bin for two weeks. There are two recommended worm-harvesting methods:
Screen Method: Place a piece of hardware cloth or window screen over the top of your worm bins. Cover the screen with food scraps and bedding and leave the bin alone for 4–7 days. The worms will sense the new food and crawl through the screen to reach the new food source. Lift the screen after 4-7 days and discover that the worms have left their castings in the bin below and have travelled through the screen.
Cone Method: Dump the entire contents of the worm bin onto a sheet or large piece of paper. Make several individual cone-shaped piles. Each pile will contain worms, compost and un-decomposed food and bedding. As the piles are exposed to light, the worms will migrate towards the bottom of the pile. Remove the top couple inches of finished compost from each little pile, separating out pieces of food and newspaper that still need to decompose more. After removing the top layer, let the piles sit under light for 2-3 minutes as the worms migrate down. Then remove the next layer of compost. Repeat this process until all of the worms are left at the bottom of the pile.
Using Worm Castings
Try to use worm compost within a few weeks to maintain nutrient values and microbial life. But the compost can be stored and used during the gardening season:
- Mix worm composting in with potting soil (1/3 of total volume) before planting.
- Side dress plants with compost throughout the season for a boost of nutrients.
- A compost tea can also be made out of worm castings and used as an organic fertilizer.
Worm-Themed Activities for Worm Bin Learning
Create a mural (on paper or using sidewalk chalk) that depicts what worms are doing under the soil. Are they eating? Are they digging? Be sure to include their expansive network of tunnels!
Use vermicompost (worm compost) to grow plants. Compare the growth rate of plants by using varying levels of casting mixtures.
Keep a worm bin journal. Track what you feed the worms and what seem to be their favorite foods. Experiment: Try putting all the the food in one corner and see if the worms migrate toward the pile!
Wiggly Worms Song (with Hand Motions)
Here are some worms who are oh so sad/ They’ve lost all the wiggles they once had/ They wonder if you, just for today/ Would lend your wiggles so they can play
Wiggle them high and wiggle them low (wiggle arms high and wiggle arms low) Wiggle them fast and wiggle them slow (wiggle arms fast and wiggle arms slow) Wiggle to the right, wiggle to the left (wiggle arms to the right, then left)
Wiggle by your shoes, wiggle by your socks (wiggle finger over shoe, and wiggle finger by sock) Then wiggle them back up to their box (have children pretend to place their worm in a box on their lap)
Francie Szostak is the Education Director for Wellspring Education Center and Organic Farm. Through Wellspring’s programs, her goal is to provide opportunities for the local community to experience and connect with where our food comes from. When not snacking in the cherry tomato patch, Francie can be found enjoying local food, music, the outdoors and embracing the culture of Milwaukee!”
About Wellspring: Wellspring is a nonprofit education and retreat center as well as a certified Organic Farm and CSA whose mission is to inspire and teach people to grow, prepare and eat healthy food. Educational opportunities are available at Wellspring throughout the year including farm tours, workshops and learning opportunities for individuals, families, school and community groups. Wellspring offers Worm Composting Classes for adults and Worm Theme Days for youth
throughout the season. Stay tuned for 2014 dates!
For more information on Wellspring’s efforts, programs and events please visit: www.wellspringinc.org