Maggots come from fly eggs. An adult fly lands on something moist and organic, like rotting food, garbage, or animal waste, and deposits a cluster of tiny white eggs. Those eggs hatch into larvae (maggots) in as little as 8 to 20 hours depending on temperature and species. The warmer and wetter the environment, the faster they appear.
Where Fly Eggs Come From
A single female house fly lays 75 to 150 eggs per cluster and can deposit 350 to 900 eggs in her lifetime. She doesn’t need much time or space. A brief landing on exposed food scraps, a trash bag with a small opening, or a pet waste pile is enough. The eggs are small, white, and often go unnoticed until the maggots have already hatched and started feeding.
Several types of flies produce maggots in and around homes. House flies breed in decaying organic matter and manure. Blow flies and bottle flies are drawn to dead animals, spoiled meat, and garbage. Flesh flies also target animal carcasses. All of these species share one requirement: the breeding material has to be moist. Larvae cannot survive in dry conditions. Research on larval survival shows that at very low moisture levels (around 5%), survival drops to zero, while wetter environments support much higher hatch rates.
Why Maggots Show Up in Trash Cans
The most common place people encounter maggots is inside a kitchen or outdoor garbage bin. Here’s the chain of events: food scraps, especially meat or dairy, start to decompose inside the bin. The smell of decomposition attracts flies. A fly slips in through a gap in the lid, an unsealed bag, or the brief moment the can is open, and lays eggs directly on the waste. Within a day, maggots are feeding and growing.
Heat accelerates the whole process. A trash can sitting in direct sunlight gets hot, which speeds up decomposition and makes the smell more intense to flies. Leaked liquid pooling at the bottom of the bin creates exactly the kind of warm, wet organic material that fly larvae thrive in. Trash receptacles with wet bottoms from leaking plastic liners are especially common breeding sites for smaller flies like fruit flies.
How Maggots Get Inside Your Home
House flies and blow flies rarely breed indoors, but they easily enter through open doors and unscreened windows. Fruit flies are small enough to pass through standard window screens. Once inside, they seek out any organic material that’s breaking down: an overripe banana on the counter, a forgotten bag of potatoes in the pantry, or a trash can without a tight lid.
One scenario people don’t always think about is a dead animal inside the walls or attic. When a mouse or bird dies in a wall void, ceiling space, or crawl space, blow flies and flesh flies find the carcass and lay eggs on it. The maggots develop out of sight, and the first sign is often a cluster of adult flies appearing inside the house days later. Unserviced rodent traps and glue boards create the same problem.
Maggots on the Body: How Myiasis Happens
In rare cases, maggots can infest living tissue. This condition is called myiasis, and it happens through a few different routes. Some flies drop their eggs directly on or near an open wound, sore, or even near the nose or ears. The larvae hatch and burrow into the skin, and certain species can migrate deeper into the body and cause serious damage.
Other flies take an indirect approach: they attach their eggs to mosquitoes, ticks, or other biting insects. When those insects bite a person, the larvae transfer to the skin. In parts of Africa, one fly species lays eggs on the ground or on damp cloth hung out to dry, like clothing or bed linens. People get infected simply by wearing the clothes or touching the contaminated surface. The primary risk factor is having untreated or open wounds, which give larvae easy access to tissue.
How to Prevent Maggots
Prevention comes down to removing what flies need: access, moisture, and decaying organic material.
- Seal your trash can. An overfilled or poorly fitting lid is an open invitation for egg-laying flies. If your bags don’t have drawstrings, double or triple knot them before tossing them in the bin.
- Rinse food containers before throwing them away. Cleaning out takeout boxes, jars, and cans removes the residue that attracts flies to your garbage and recycling.
- Keep outdoor bins in the shade. Heat speeds up decomposition and intensifies the smell that draws flies. A cool, shaded spot makes your trash far less attractive.
- Clean the bin regularly. Wipe it out with a sanitizing solution every few weeks. If maggots have already appeared, a mix of one part white vinegar to three parts hot water, poured in and left for 30 minutes with the lid closed, will kill them. Rinse and repeat with the same solution to deodorize.
- Separate food scraps. Composting or recycling food waste keeps the primary maggot food source out of your trash entirely.
For indoor prevention, check for dead animals if you notice a sudden spike in flies, especially blow flies or bottle flies. Inspect attics, crawl spaces, wall voids near rodent entry points, and any traps you may have set. Removing the carcass eliminates the breeding site immediately.