A Restaurant Guide for the Discerning Worm

Red wiggler composting worms are not terribly picky about what is on the menu. However, knowing what to feed and what to avoid ensures that your red wigglers thrive in your composting bin.

First, a word from our sponsor: Worm Works offers the very popular 'Worm Stampede Feed' which worms love. The feed pellets dissolve in the bin and provide a complete nutrition for your red wigglers. Unlike kitchen scraps, Stampede Feed stores almost indefinitely and can be used any time your scraps run low. See our blog post and product page for more information on how to order and use Stampede Feed.

Bedding

Bedding is the edible (but not necessarily nutritious) environment your worms live in. Since composting worms are primarily a cow manure worm, the bedding should mimic a slightly aged, slightly dried cow patty in-the-field: full of broken down plant material with just the right amount of moisture. Shredded newspaper, cardboard, and coconut coir are perfect examples as they hold moisture, allow for air exchange, and provide some nutrients. For worms to thrive, they must still be fed in addition to the bedding.

Household and Yard Sources of Food

Red wigglers are voracious eaters and will consume a variety of household and yard waste. Kitchen scraps such as fruit and vegetable peels, coffee grounds, and eggshells are great sources of food and vitamins for your worms.

A key concept for feeding is that worms can't eat, for example, an apple. The apple must first be broken down (rotted) to the extent that microbes are actively consuming the rotten flesh. In typical conditions, an apple takes 3 weeks to become worm food. So, when you put an apple in your bin, you are feeding them several weeks in the future. In comparison, Stampede Feed is worm-ready in just a few hours after it lands in the bin.

A very effective strategy for delivering kitchen scraps is to freeze the waste first. This breaks down the cell walls of plant material which makes the nutrients accessible to microbes and worms faster. Yard waste such as leaves and grass clippings, in moderation, can also be added to the composting bin.

Kitchen Scraps to Avoid

While red wigglers will consume a variety of kitchen scraps, there are some materials that should be avoided. Meat, dairy, and oily foods should not be added to the composting bin as they can attract pests and create unpleasant odors. They also break down much more slowly and will sit in the bin for a long time before worms can consume it. Additionally, materials such as citrus fruits, onions, and garlic are too acidic for the worms and should not be added at all. A general rule of thumb is that if a food would sting your eyes if it came in contact, worms will avoid it.

Bedding to Food Ratio

Both bedding and food break down over time and are consumed by the worm. A primary function of bedding is to maintain moisture and airflow while allowing the worm to move from food source to food source. Too much food material will likely become anaerobic which is a smelly, toxic environment for your bin. For every pound of kitchen scraps added, include 2 pounds of bedding. That ratio will keep air flowing around the scraps.

How to Know When and How Often to Feed

Adult red wigglers are capable of consuming up to half their weight in food each day, but it is important not to overfeed them. In general, feed your worms every 3-5 days and only add as much food as they can consume in that time. To know when to add more food, check the composting bin and see if there is still food left from the previous feeding. If there is no food left, it is safe to add more.

Moisture

Finally, and somewhat related, is moisture. Worms breathe through their skin and require moisture for transpiration and locomotion. The food you add will likely include a certain amount of moisture. Monitor moisture levels often. When you take a handful of bedding/casting from the bin, you should be able to squeeze out a single drop...and no more.