My Compost Worms Aren't Eating - 5 Common Causes & What to Do
If you've farmed compost worms or managed a worm compost bin for a few months or more, you’ve likely encountered a situation where your red wigglers aren't eating.
In some cases there may be nothing wrong in the bin if the worms aren’t eating, but usually uneaten food is a sign that there is a problem with the compost worms. If you find yourself faced with worms being sluggish or not eating, the most likely problems are a low worm population in your bin, hot or cold air temperatures causing the worms to slow down, or feeding practices that need to be adjusted.
Worms Aren’t Eating - 5 Most Common Problems
If the worm compost bin is a new one you recently set-up, keep in mind it can take red wigglers 3-7 days to get acclimated in their new home and interested in eating. This is not a big problem as the worm bin bedding serves as a food source, so it's unlikely the worms will die of starvation within a week or 2.
In the early stages of a new worm bin, we recommend being patient and adding only a small amount of food (e.g., 3-4 ounces of food per pound of compost worms) to the bin. Within a few days the worms should show interest in the food and begin their feasting.
If you have a more established bin (a month or more in age) of compost worms and red wigglers and the worms aren't eating, there are 5 simple items to address first:
1. Worm Population: The first thing to check for when worms stop eating is whether or not there are still worms in your bin! The compost worms may have died or, if your worm farm is outside, may have left for areas nearby. If there are no, or few, worms left, you’ll likely need to buy more red wigglers and start a new bin.
2. Is the Bedding Fully Processed into Castings: Red wigglers and compost worms can not live in their poop (i.e., worm castings) for too long - the castings are toxic to them and will slowly deplete your population of worms if left unaddressed. Red wigglers will grow lethargic and slowly die out if left in their castings for too long.
If it has been 2-3 months since you started your bin, or if the bedding in your worm farm or worm compost bin is fully processed into castings, there are 3 options to address worms not eating:
1 - Add 1-2 inches of new worm bin bedding on the surface of the bin and begin feeding your worms again, or
2 - Sift the worms from the bedding/castings (a ⅛ inch screen works great) and start a new tray with fresh bedding and food, or
3 - If you have a stackable worm bin with multiple trays, remove all food from the fully processed tray, add fresh bedding to a new tray, place the tray above the fully processed tray, and feed only in the new tray (the compost worms should migrate to where the food is).
Pro tip: We recommend options 2 or 3 :)
If this is the case, reduce the amount of food until the worms start eating again and move the bin to a more optimal temperature range (e.g., 60-90 degrees).
Also, this is a good time to note that compost worms will eat different amounts of food based on the season and temperature, so when temps get hot or cold you’ll need to adjust how much you are feeding your worms!
It's important to remember that worms are attracted to water, so a bin should be the most moist on the surface, and then get gradually drier further down in the bedding. If the bin is too dry, mist the top of the bed thoroughly to add consistent amounts of moisture to the bin. If the bin is too wet or has standing water in the bottom of the tray, remove the excess liquid from the tray, remove all food and then mix in additional bedding to absorb some of the excess liquid.
For more on how to water your worm bin, check out our Guide to Watering Your Worm Bin (spoiler - most people over-water!).
5. Feeding Practices: "How" and "what" compost worms are fed can impact their feeding patterns. It's important to make sure the menu you are serving is something compost worms are interested in.
The good news is that worms can eat just about anything, so finding something they will eat is usually not too tough. That said, if the worms aren't eating, try feeding them small amounts of fruit (but limit citrus) like bananas, berries or chopped-up avocado.
Worms are Sluggish or Aren’t Eating - Other Causes
If worm population, bedding, temperature, moisture, and feeding practices are not the issue, there may be something more serious going on inside the worm compost bin. These issues can include pH problems or anaerobic conditions. If you suspect these conditions are to blame, we recommend the following steps:
- Composted horse or dairy manure,
- Composted fruit and vegetable waste,
- Fully composted leaves and grass clippings,
- Peat moss or topsoil from your yard (avoid store-bought soils),
- Shredded cardboard
Pro Tip - Mix shredded cardboard in (1:3 ratio) with any of the above options, your worms will love the additional carbon source!
4 - Lightly water the bedding so that when a handful is squeezed, only a few drops wring out.
5 - Add rinsed, crushed egg shells from 1-2 eggs to the new bedding.
6 - Apply the new bedding in a layer on the surface of the bin. If you have other trays available in your worm farm, you can also use these steps and create an entirely new tray that the worms can migrate to.
7 - Add a small amount of feed (e.g., fruit) to 1-2 areas on the surface of the bin.
It may take several more days for the worms to begin feeding, but they should start to recover within a week or 2.
If the above recommendations don't address the issues in your worm bin, check out the other articles in this series on troubleshooting worm bin issues and common worm composting problems, or reach out to us at email@example.com and we're happy to help!