Raise them in a closed bin, not out of the yard. Buy red wigglers from a worm grower, keep them in a dark plastic bin with a lid, and feed them raw fruit and vegetable scraps under damp shredded paper. Then keep chicken droppings, coop litter or run dirt from ever getting in. That last part is the whole reason to bother. Earthworms from the ground can carry gapeworm and cecal worm larvae for years, and the Merck Veterinary Manual names them as one way a flock picks those up.
I rewrote this page from nine sources, and you’ll find every one listed at the bottom. The bin itself comes from NC State Extension’s worm guide and Cornell’s worm composting basics. The parasites come from two chapters of the Merck Veterinary Manual. For worms as food I read Feedipedia’s page on earthworm meal, the 2001 study behind its warning about worm fluid, and a 1982 Edinburgh thesis on feeding worms to poultry. Colorado State and Alabama Extension gave me how much a hen eats and how much of that can be treats. Nobody I read tested a closed worm bin for chicken parasites, though. So where I say the bin keeps them out, that’s my reasoning from how Merck says they spread, and I’ll say so each time.
The short version.
- Worms. Red wigglers (Eisenia fetida) from a worm grower. NC State says not from a bait shop or your yard.
- Bin. Dark plastic with a lid, air holes high on the sides. About 2 feet by 1 foot for 2 pounds of scraps a week. Keep it in the shade, at 59 to 77°F.
- Bedding. Black-and-white newspaper or cardboard torn into half-inch strips, damp enough that a squeeze gives you 2 or 3 drops.
- Food. Raw fruit and vegetable scraps, no more than an inch deep, buried under bedding. No citrus, meat, dairy or grease. And never chicken droppings or litter.
- Harvest. After about 3 to 5 months. Stop feeding for two weeks, then let light push the worms down.
- Serving. Treats are 10% of a hen’s daily food at most, so 10 to 15 grams of worms. By my math that’s about a gram of protein. It’s a treat, not a cut in the feed bill.
Why Not Dig Them Up
Here’s the part I see skipped most. The worms in your yard aren’t clean. The Merck Veterinary Manual’s chapter on worms in poultry lists earthworms as a host for gapeworm and for several Capillaria species. The cecal worm, Heterakis, uses them too. In Merck’s words: “Heterakis larvae will translocate into the coelomic cavity of the earthworms and remain alive for years.” Gapeworm is no better. Merck says “many gapeworm larvae may encyst and survive within a single invertebrate for years.”
So how do the larvae get into a worm? Merck says earthworms “may ingest the eggs of the cecal worm.” It also says the eggs of the cecal worm and the big roundworm “can survive up to two years in soil.” Put those together (my reasoning, not Merck’s) and the worms most likely to carry larvae are the ones living under your run. Spring makes it worse. Merck says these infestations may climb when there are “large numbers of earthworms brought to the surface by spring rains.”
Gapeworm is the one I’d worry about with young birds. Merck says “young birds are the most severely affected,” and lists “gasping, choking, shaking of the head” as signs. It also says gapeworms “are not a problem in confinement-reared poultry,” but they cause serious losses in range-reared chickens. And it calls worm infections like these “common in ranged birds and in backyard flocks.” That’s pretty much all of us.
If you keep turkeys, this matters even more. The cecal worm carries the blackhead parasite, Histomonas. Merck’s blackhead chapter says “three species of earthworms can act as paratenic hosts” for cecal worm larvae carrying it. Chickens are usually carriers that don’t look sick. In turkeys, Merck puts deaths at “commonly 80%–100%,” and says “there are no approved treatments or vaccines.” Its advice is plain: “turkeys should not be put on ground contaminated by chickens.” To my mind, a bucket of worms dug out of the chicken run is that ground, brought to them.
NC State’s worm guide has a simpler reason to skip the yard. You can’t tell which species you’ve dug up. And Feedipedia, a livestock-feed database, says earthworms “are commonly consumed by poultry in free-range rearing systems.” So a hen out on the lawn already eats yard worms. You can’t stop that, and I wouldn’t try. What I won’t do is dig up more for her. Our post on whether chickens can eat frogs goes through the other small critters on Merck’s list.
Buy Red Wigglers
NC State Extension’s Rhonda Sherman says there are “more than 9,000 species” of earthworms, and only 7 have been found to suit worm composting. The one you want is Eisenia fetida, the red wiggler. Cornell’s worm guide names it along with Lumbricus rubellus. Cornell also says red wigglers live near the surface, in the top 6 inches of soil. That’s why its bin “should be shallow rather than deep.”
Where you get them matters. NC State is blunt about it: “Do not get the earthworms from a bait shop (you would need to buy 33 to 38 bait cups!) or your yard (how could you tell what species is Eisenia fetida?). Instead, buy them from a worm grower.” The bait counter may not even have the right worm. Feedipedia says the African nightcrawler “is also extensively used as fishing bait in North America,” and it can’t be raised outdoors outside the tropics and subtropics.
How many? NC State says at least one pound of red wigglers, about 1,000 worms, for each square foot of bin. A 2-by-1-foot bin takes 2 pounds. And if your worms don’t look quite like the picture on the box, you’re not alone. Feedipedia says Eisenia andrei and Eisenia fetida “are quite similar (red striped worms) and often confused.”
The Bin
NC State sizes a bin by your scraps: one square foot of surface for each pound of food scraps you make in a week. Two pounds a week means a bin about 2 feet by 1 foot and 8 to 20 inches deep. Cornell’s classroom bin was about 24 by 18 by 8 inches, so they’re in the same ballpark. Get a dark one. NC State says “earthworms are highly sensitive to light.”
Air holes go high on the sides, near the lid. “Do not drill holes in the lid,” NC State says. You’ve got a few choices for the sides: a 3-inch screened soffit vent at each end, four half-inch holes, or a bunch of eighth-inch holes. Then drill six quarter-inch holes in the bottom, spread out, for drainage.
Now where it lives. NC State’s list runs from a garage or carport to a porch, deck, kitchen or basement. Outside, it has to be a spot that’s “always shady.” Never put it in direct sun, which “can cause the system to overheat and kill your earthworms.” The worms like it between 59 and 77°F (15 to 25°C), and NC State’s limits are 32 and 95°F. In winter, NC State says to put blueboard insulation on the outside walls or pack straw around the bin. Or cut a gallon jug in half, fill it with water, put an aquarium heater in it and set it inside the bin. In a hot spell, mix in some dry bedding or set a container of ice in the bin.
One more thing, and this one’s mine, not NC State’s. Keep the bin out of the run and off the coop floor. The whole point is a bin that no chicken droppings can reach. A lid that stays on, in a spot the flock can’t scratch at, is the easy way to keep it that way.
Bedding
Your worms live in damp paper. Here’s what NC State says works:
- shredded black-and-white newspaper, paper bags, office paper or cardboard
- decaying leaves
- coir
“Do not use glossy paper or magazines.” Tear the paper into strips about half an inch wide and soak them for 5 to 10 minutes. Then squeeze a handful. NC State says “only two to three drops of water should come out.” Fill the bin about halfway. Then leave it be. “Never pour water into your worm bin!” NC State says, and don’t stir or turn it either. Its table puts the moisture at 80%, with a pH above 5 and below 9.
NC State also says to mix in “a handful of soil from a healthy garden.” Here’s where I’d be picky. Take it from a bed your hens never get into, or skip it. Merck says those roundworm and cecal worm eggs last up to two years in soil, so the run is the last place I’d scoop from.
And keep chicken litter out of the bedding. Parasites aren’t the only reason. Feedipedia says “poultry litter is less appreciated” for raising worms “due to its high temperature and high protein content, which can be deleterious to earthworms.” Turns out the worms don’t want it either.
What Goes In
Cornell keeps it simple: “We recommend using only raw fruit and vegetable scraps.” NC State’s yes list is a bit longer:
- vegetables and fruits
- crushed eggshells
- tea bags and coffee grounds
- shredded paper coffee filters
- shredded garden debris
NC State says red wigglers are especially fond of melon (cantaloupe or watermelon) and pumpkin. Here’s its no list:
- citrus fruits or peels, which can make the bin “too acidic”
- meat scraps or bones, or fish
- greasy or oily food, or fat
- onions or garlic
- salty foods
- tobacco
- pet or human manure
Cornell says to stay away from dairy too, and that citrus “can attract fruit flies.” Onions and broccoli “tend to have a strong odor.” I’d add chicken droppings and coop litter to that manure line, for the reasons above. And if you’re wondering which scraps your hens can have straight, our list of what not to feed chickens covers that side.
How much at a time? NC State says a feeding “should not exceed 1-inch high,” and you cover it “completely with 1 to 2 inches of bedding.” Don’t add more till the worms have finished the last batch. NC State says a bin can be fed “as seldom as every two to three weeks.”
The sources don’t agree on how fast worms eat. NC State says “one pound of red wigglers will eat up to two pounds of food scraps a week.” Feedipedia says earthworms can eat “50 to 100% of their body weight in one day.” For that same pound of worms, that’s 3.5 to 7 pounds a week. Feedipedia is a feed database writing about worm farms, and NC State is writing for a bin at home. I’d start with NC State’s number and go by the bin. If last week’s food is still sitting there, they’re full.
Harvest Day
NC State says that “in about four months, it will be time to harvest.” Cornell says after 3 to 5 months, once the bin is mostly compost. Close enough. And don’t put it off. Cornell says the castings, “at high concentrations, create an unhealthy environment” for the worms. Its hands-on way is the one I’d try first. Stop adding food for two weeks. Then dump the whole bin onto a sheet of plastic or paper in the light and heap it into cone piles. Scrape off the top, let each pile “sit under light for 2-3 minutes as the worms migrate down,” and scrape again. Keep going till the worms are bunched at the bottom. Cornell puts them back in the bin with fresh bedding (minus the ones your hens get, in our case).
NC State gives three ways:
- Sideways. Feed on one side of the bin only, for several weeks. The worms move over to the food, and you take the other side.
- Light. Same idea as Cornell’s. Wait five minutes, scrape off the top layer, and you’ll find worms in clusters you can just pick up.
- Vertical, with stacked bins.
Watch for the capsules. NC State says they’re “lemon-shaped and about the size of a match head,” shiny and light brown. Each one holds two to seven baby worms, by NC State’s count. Cornell says 2 to 5, and that the babies stay inside for at least 3 weeks. I’d put every capsule back in the bin. Cornell says a worm lives about a year in a bin, so those babies are the bin’s next round.
What’s left is worm compost for the garden. NC State has one warning if you make a tea from it: “Do not use vermicompost tea on the edible portion of a plant unless you are absolutely certain that the solution does not contain pathogens.”
How Many a Hen Gets
Here’s the math, and it’s mine, from the sources’ numbers. Colorado State Extension says treats “should make up no more than 10% of their daily diet.” It also says not to feed more than they’ll eat in 5 to 10 minutes, so you don’t draw in nuisance animals. Alabama Extension says a laying hen eats 100 to 150 grams of feed a day, about a quarter pound. Ten percent of that is 10 to 15 grams of worms per hen per day. If you’d like your own flock’s number, our Chicken Feed Calculator works out the daily feed.
Worms sound like a protein bomb, and dried, they are. Feedipedia’s table puts dried earthworm at 57.9% crude protein on average, over 46 samples. S. P. G. White’s 1982 Edinburgh thesis found 60.63% in air-dried red wigglers. But a live worm is mostly water. Cornell says about 90%, and Feedipedia gives 11.6 to 15.2 grams of dry product from 100 grams of fresh worms. So 10 to 15 grams of live worms is about 0.7 to 1.3 grams of protein. Her layer feed, at Alabama’s 16% protein, gives her 16 to 24 grams a day. So the worms come to 3 to 8% of what her feed gives her.
Now the bin. Start NC State’s 2-by-1-foot bin with 2 pounds of worms. Feedipedia says a worm population “under favorable conditions may double within 30-60 days.” At that best case you’d have about 2 pounds of spare worms every one to two months, or 15 to 30 grams a day. Six hens’ treat room is 60 to 90 grams a day. So one bin at its best covers somewhere between a sixth and a half of their treats, and it barely touches the feed bill. Honestly, that’s fine. It’s a treat jar that eats your kitchen scraps.
Do worms hurt laying? Feedipedia cites a 1979 study by Mekada and colleagues. Fresh earthworms fed at 5% of the diet’s dry matter kept laying going, and “egg quality was not degraded.” By my math that’s about three or four times a treat-sized portion of worms.
You might also read that worm body fluid is toxic. Feedipedia says it’s “toxic to vertebrates,” birds included, and that heating fixes it, “hence the necessity of blanching the earthworms.” But look at the study behind that, by Kobayashi and colleagues in 2001. The quail and other animals died after the fluid was injected into a vein. It wasn’t a feeding test. Mekada’s hens ate fresh worms, and free-range hens eat raw ones all day. So I don’t see a reason to cook a few treat worms. Blanching makes more sense if you’re drying worms into a meal, which is what that Feedipedia page is about.
Last, metals. Feedipedia says earthworms “are able to accumulate a number of metals in their body,” with cadmium and lead building up more easily, depending on what’s in the stuff they live in. That’s one more reason I’d pick worms raised on kitchen scraps over worms from soil I know nothing about. And with chicks, keep Merck’s gapeworm warning in mind. I’d give young birds no yard worms at all. For the rest of a laying hen’s diet, our Rhode Island Red feeding guide goes through the feed tags.
Sources
- Rhonda Sherman, NC State Extension: Worms Can Recycle Your Garbage (AG-473-18, March 29, 2017).
- Jen Fong and Paula Hewitt, Cornell Waste Management Institute: Worm Composting Basics (1996).
- Rüdiger Hauck, Merck Veterinary Manual: Helminthiasis in Poultry (reviewed January 2024, updated May 2025).
- Robert Beckstead, Merck Veterinary Manual: Histomoniasis in Poultry (reviewed March 2024).
- Heuzé and colleagues, Feedipedia: Earthworm meal (updated November 3, 2020).
- Kobayashi and colleagues: Toxicity of coelomic fluid of the earthworm Eisenia foetida to vertebrates but not invertebrates (Comparative Biochemistry and Physiology Part C, 2001; I read the abstract).
- S. P. G. White: Earthworms as a Feed for Poultry (thesis, University of Edinburgh, 1982).
- Colorado State University Extension: Raising Poultry the Organic Way, Disease Control and Feeding.
- Alabama Cooperative Extension System: Feeding the Laying Hen (ANR-2913).
Sources checked October 27, 2026. The grams of worms, the protein and the bin’s yield are my math from the sources’ own numbers. The closed bin is my reasoning from how Merck says these parasites spread, since no source I read tested one. We aren’t vets. If a hen looks sick, call a vet who sees poultry.
Related read: How to Raise Chickens for Eggs — Instant PDF download. Secure checkout by Stripe
