Raising mealworms for chickens is straightforward, inexpensive, and takes about 10 to 12 weeks from egg to harvestable larva. All you need is a few plastic bins, some wheat bran, a handful of vegetables for moisture, and a warm spot in your home. Once a colony is established, it cycles continuously, giving you a steady supply of high-protein treats your flock will devour.
What You Need to Get Started
The simplest setup uses three smooth-sided plastic bins (roughly 12 to 16 gallons each), one for each active life stage: larvae, pupae, and beetles. Smooth sides matter because mealworms can’t climb them, so no lids with ventilation holes are strictly necessary, though a mesh lid helps with airflow. Drill or melt small holes in the lid if you use one, keeping them too small for beetles to escape.
For bedding, fill each bin with 2 to 3 inches of wheat bran. Oats, cornmeal, whole-grain cereal, or coarse whole wheat flour all work as alternatives. This substrate doubles as their primary food source, so you’ll replenish it as they eat through it. Avoid anything with added sugar or salt.
To start your colony, order 500 to 1,000 live mealworms from a pet supply store or online insect breeder. You can also buy a small batch of darkling beetles if you want to skip ahead in the life cycle. A mixed-age starter colony gets you to a self-sustaining population faster.
The Mealworm Life Cycle
Understanding the four stages helps you manage timing and know when to separate your bins. Female darkling beetles lay tiny white eggs in the substrate, often invisible to the naked eye. These hatch in one to four weeks depending on temperature. The larvae that emerge are the mealworms you’re after. Under ideal conditions, the larval stage lasts about eight to ten weeks, during which they molt repeatedly and grow to roughly an inch long. When they’re ready to pupate, they curl into pale, motionless comma shapes. Two to three weeks later, adult beetles emerge, initially white before darkening to brown and then black. Those beetles begin laying eggs within a week or two, and the cycle restarts.
The entire egg-to-beetle cycle runs roughly three to four months. Once you have all stages running simultaneously in separate bins, you’ll have harvestable larvae on a rolling basis.
Temperature and Humidity
Mealworms grow fastest at 75 to 80°F (24 to 27°C). Below 70°F, growth slows noticeably. Below 60°F, reproduction nearly stops, which is actually useful if you want to refrigerate a batch to slow them down for storage. Above 85°F, mortality climbs.
Humidity should sit between 50 and 60 percent. Drop below 45 percent and you’ll see dehydrated worms, lower egg production, and dead pupae. Worms that are actively molting are especially vulnerable to dry conditions. If your home runs dry, the moisture vegetables described below become even more critical. A simple hygrometer placed near your bins helps you monitor conditions without guessing.
Feeding and Moisture
The wheat bran substrate is their main food. As they eat it down, add more to maintain that 2- to 3-inch depth. You can supplement with small pieces of whole meal bread or plain biscuits for variety, but bran or oats should remain the staple.
Mealworms get all their water from fresh produce. Carrots are the go-to choice because they release moisture slowly and resist mold longer than softer options. Potato slices work similarly. Lettuce, napa cabbage, and white radish are also commonly used on mealworm farms, though leafy greens dry out faster and need replacing more often. Cut produce into thin slices and lay them directly on the substrate surface.
Replace vegetable pieces before they get slimy or start to mold. In warm conditions, that means every one to two days for leafy greens and every three to four days for carrots or potatoes. Many small-scale keepers only provide a single lettuce leaf twice a week, which is often not enough. Err on the side of offering produce more frequently in smaller amounts rather than large pieces that sit and rot. Excess moisture in the bin invites fungal growth, increases larval mortality, and degrades the feed substrate. Pools of standing water can actually drown mealworms. The goal is damp produce on dry bedding.
Separating Stages and Harvesting
Keeping life stages separated is the single most important management task. Beetles will eat eggs and small larvae if left together. Every week or two, move any pupae you find into the pupa bin. Once beetles emerge from that bin, transfer them to the beetle bin where they’ll lay eggs into fresh substrate. After two to three weeks, move the beetles to a new tray of substrate so they don’t consume their own eggs. The old substrate, now full of microscopic eggs, becomes your next larva-growing bin.
Harvesting larvae is as simple as scooping them out of the substrate. A fine-mesh kitchen sieve or a piece of window screen over a bin works well for separating worms from the bedding and frass (the fine, dark waste they produce). Sift gently. If your worms are still small, wait until they bulk up before sifting aggressively, since tiny larvae fall through the screen with the frass. Some keepers use a shop vacuum held a few inches above the surface to pull off shed skins and frass dust without sucking up the worms themselves.
Clean out frass buildup every few weeks. It compacts, holds moisture unevenly, and can harbor grain mites if left too long.
Dealing With Grain Mites
Grain mites are the most common pest in mealworm colonies. They appear as a fine, moving dust on bin walls and substrate, and they thrive in the same warm, moderately humid conditions your mealworms need. Prevention starts with keeping bins clean, not overwatering produce, and storing bulk substrate (bags of wheat bran or oats) in sealed containers.
If mites appear, wipe down bin walls frequently with a damp cloth to physically remove them. An effective home remedy used by experienced mealworm farmers is adding powdered green split peas to the substrate. Grind dried split peas into a fine powder and mix a few cups into each affected bin. This disrupts the mite population without harming mealworms. Keeping humidity at the lower end of the acceptable range (closer to 50 percent) also discourages mites while still supporting your colony.
Nutritional Value for Chickens
Live mealworms are about 20 percent protein, 13 percent fat, and 62 percent moisture. Dried mealworms concentrate those nutrients dramatically: 53 percent protein and 28 percent fat. Either form makes an excellent protein supplement, especially during molting season when hens need extra protein to regrow feathers, or during cold winter months when energy demands increase.
That fat content is worth paying attention to. Mealworms are rich enough that they work best as a treat or supplement, not a dietary staple. Research on laying hens suggests that mealworm meal is safe and effective at 2 to 5 percent of the total diet. Beyond that, the high levels of fat and certain amino acids can start to reduce digestibility and affect blood markers. In broiler chicks specifically, inclusion rates above roughly 10 percent of the diet reduced immune function markers and lowered overall growth performance. The chitin in mealworm exoskeletons also becomes harder to digest at higher quantities.
A practical guideline: treat mealworms like any other high-value snack. A small handful per bird per day is plenty. Your chickens’ regular layer feed should remain the foundation of their nutrition, with mealworms as a protein-rich bonus.
Scaling Up Your Colony
Once your three-bin system is running, scaling is just a matter of adding more bins. Many backyard chicken keepers run five to ten bins stacked on shelving in a garage, spare closet, or heated shed. A small flock of six hens won’t need more than a few thousand larvae per week as treats, which a modest colony of three to four active bins can sustain after the first generation matures.
Label your bins with dates so you can track which batch is closest to harvest size and which substrate trays are incubating eggs. Rotate beetles to fresh substrate every two to three weeks for maximum egg production. The beetles typically live two to three months and lay throughout their adult lives, so a healthy beetle bin keeps your pipeline full without needing to buy new stock.
The startup cost is minimal: a few dollars for bins, a bag of wheat bran, and your initial worm order. After that, the ongoing cost is essentially just bran and vegetables. Most keepers find the colony self-sustaining within one full life cycle, roughly three to four months from setup to a perpetual harvest.