How to Maintain a Worm Compost Bin

Worm bins are tubs that are filled with soil, worms and table scraps. As you add food items to the bin the worms feed on it, digest it, and turn the matter into dark, fertile compost that can be used in your garden or flower beds. Worm bins are highly effective ways to compost and result in usable soil quicker than a traditional compost pile. When properly maintained, worm compost bins can be kept indoors as well as outdoors.

Things You'll Need

• Thermometer
• Soil pH tester
• Lime
• Vegetables, fruit, coffee grounds, tea and other organic matter
• Window screen
• Wheelbarrow or large bin
• Shredded newspaper
• Water

Instructions

1. Place a thermometer directly beside the compost bin and ensure that it maintains a constant temperature of between 55 and 77 degrees Fahrenheit. According to Washington State University, worms start to die above 84 degrees Fahrenheit.

2. Insert the metal probe of a soil pH tester into the worm bin once or twice per year to ensure that the pH level is close to 7. If the soil is too acidic, add in 1/4 cup of eggshells or limestone and mix it in well. Retest the soil once per week until the proper pH level is achieved.

3. Add vegetable and fruit peelings, coffee grounds, tea and any other organic matter to the worm bin as you accumulate it. Dig a hole along the side of the container and bury the food in the middle of the existing compost. Rotate locations so that you do not add scraps to the same location each time.

4. Remove all existing soil every two to three months. Place a window screen on top of a large bin or a wheelbarrow and scoop handfuls of the compost on top of it. Press down gently to sift the compost through the screen. Move the worms to one side so you can place them back into the bin.

5. Refill the bottom of the bin with 3 to 4 inches of shredded newspaper and then spray it with water until it is moist but not soggy. Place an additional 1 inch of soil or compost on top of the newspaper and then place the worms back into the bin.

Tips & Warnings

• Place 1 lb. of food per day into the bin for every 2 lbs. of worms that are in it.

• Never put meat or dairy items into the worm compost bin.

References

• City Farmer: Worm Composting
• Washington State University Extension: Composting with Redworms