Vegetable peels and coffee grounds are excellent for compost, but adding meat, bones, or greasy foods can quickly turn your compost pile into a magnet for rodents, insects, bears, and other critters.
Keeping pests out of your compost pile is important for maintaining a healthy, odor-free system and preventing infestations that could spread to your home and garden. Simple methods like using a 3:1 ratio of browns and greens, turning the pile regularly, and burying food scraps under dry materials can help.
This guide will teach you my favorite tricks for keeping pests out of your compost pile. However, if your issues persist, don’t hesitate to contact a local Lawn Love pro to resolve your pest problem.
Ways to pest-proof your compost
Keeping pests away from compost prevents the spread of diseases and bad odors. It also helps maintain a healthy balance of beneficial microorganisms for proper decomposition.
Pest issues can be a concern, but they are manageable. Simple steps like choosing the right container, avoiding pest-attracting materials, and keeping the compost at the right moisture can help keep unwanted visitors away.
Use the right container
An open compost pile is an invitation for pests. To keep them out, choose a sturdy, hard-sided compost bin made of metal or thick plastic with a secure lid.
Compost tumblers, which are enclosed containers mounted on a stand for easy turning, are another great option since they make turning the pile easy. Even a clean plastic garbage can with drilled ventilation holes and a secure lid works well — just add a hinged door near the bottom for harvesting finished compost.
Whatever container you choose, ensure all sides (including the bottom) are protected against burrowing animals with wire mesh, and maintain at least 2 feet of clearance from wooden structures on your property.
Want to know more about compost bins? Check out our guides:
Layer your materials properly
A well-constructed compost pile generates sufficient heat in the center to naturally deter pests. The key is to maintain the right balance of materials: a 3:1 ratio. Combine three parts of browns, such as dry leaves, cardboard, and straw, with one part of greens, like fruit scraps and coffee grounds. This ratio helps maintain proper carbon/nitrogen balance and prevents odors that attract animals.
Additionally, begin and end with a layer of browns. When you add food scraps, be sure to cover them with browns right away to minimize pest attraction.
My tip: Moisture is important when layering. I’ve realized that watering each layer as I add it is easier than trying to dampen the pile after it is completely built.
Read more: How to Use Compost in Your Lawn and Garden
Avoid materials that attract pests
Not everything organic belongs in your compost pile. Some materials can attract pests or slow down decomposition. Here are some of the most common items to avoid:
- Dairy products: Milk, cheese, and yogurt produce strong odors that attract rodents and flies.
- Bones and meat: These take a long time to break down, smell bad as they decay, and draw scavengers like raccoons and rats.
- Oil and greasy food: Fats don’t break down well in compost, create foul smells, and can coat materials, slowing decomposition.
- Pet feces: Waste from dogs and cats can contain harmful pathogens and parasites that make compost unsafe for gardening and attract rodents.
- Bread and other baked goods: These attract rodents and insects looking for an easy meal.
- Citrus peels: While small amounts are fine, too much citrus can make the compost overly acidic and may deter beneficial worms.
- Disease plants: Infected plant material can spread fungi, bacteria, and other pathogens, contaminating your compost and future garden soil.
Read more: What Can And Cannot Be Composted
Maintain proper moisture
Your compost should be damp, not soggy. It should be like a damp sponge. Too much moisture can block airflow for materials to break down properly, which leads to bad odors that attract pests. On the other hand, if it’s too dry, the decomposition process slows down.
A simple way to test moisture levels is the squeeze test: grab a handful of compost and squeeze it. It should feel damp and release only a few drops of water. If water drips out easily, it’s too wet.
Check moisture levels at least once a week and adjust as needed to keep decomposition running smoothly. If you have moisture issues, here’s what to do:
| Too wet | Too dry |
| Add browns (like dry leaves or shredded paper) and turn the pile. | Add water and turn the pile to help it absorb the moisture. |
Turn your pile regularly
Turning the compost regularly is the best way to keep pests away. Compost needs oxygen to break down, and a well-aerated pile decomposes faster. Use a pitchfork to turn the pile once a week during summer and once every few weeks during winter. After turning, cover the top with a layer of brown materials to help control odors and discourage pests from digging in.
Frequent turning disrupts nesting sites, making it harder for pests like rodents to settle in. It also redistributes food sources, preventing scraps from sitting on top where they can attract animals. Turning also increases temperature levels which helps speed up decomposition and creates an environment too hot for pests to tolerate.
Signs your pile needs turning:
- Matting or compaction: If layers of food scraps or leaves stick together, airflow is reduced, and decomposition slows down.
- Strong odors: A rotten or sour smell can mean the pile is too wet and needs aeration.
- Lack of progress: If your compost looks the same week after week, turning it can help speed decomposition.
Create physical barriers
An effective way to keep rodents and wildlife out of your organic compost is by using a physical barrier like wire mesh or hardware cloth. Most store-bought compost bins are designed to keep specific pests out, but if you need extra protection, wrapping the bin in hardware cloth can block any unnoticed opening.
“A sheet of 1/4-inch hardware cloth a few inches larger than the bottom opening of your compost bin will serve as a barrier against small rodents that tunnel from underground,” explains Nadie Vanzandt, a master gardener with the University of Vermont Extension.
If your compost is placed directly on the ground, placing a layer of wire mesh underneath before building your pile will stop burrowing rodents, such as rats, from entering from below. However, it’s equally important to secure the sides of open compost piles with hardware cloth to prevent pests from squeezing through gaps.
My tip: Check your barriers regularly for damage. I recommend inspecting the mesh once a week and patching up any holes or gaps to keep your compost protected.
Pick the right location
When selecting a spot in your yard for your composter, pick a level area with good drainage, especially if you have an open pile, to avoid excess moisture at the bottom. The location you select should be easily accessible year-round, allowing you to add materials and turn the pile regularly (about once a week in warmer months and every few weeks in colder months).
- Partial sunlight: Compost breaks down better in a partial sunlight spot as too much sun can dry it, and too much shade can slow the decomposition process.
- Away from your house: Keep your compost 10 to 20 feet away from your house to minimize any potential odor issues and reduce the chances of attracting pests too close to your home.
- Avoid placing your bin against walls, fences, or dense vegetation: These areas provide shelter and pathways for rodents. Instead, choose an open space where pests have fewer places to hide.
- Out of high-wind areas: Strong winds can dry out the pile too quickly, slowing decomposition.
Use natural deterrents
Natural deterrents can help keep pests away from your compost, but they should be used with caution. Many strong scents and substances that repel rodents and insects can also harm beneficial microorganisms, worms, and bugs that help with decomposition. To avoid this, it’s better to use these deterrents around the compost pile than inside of it.
My tip: Natural deterrents must be reapplied regularly, especially after rain, as water can wash them away and reduce their effectiveness. In dry conditions, reapplying every 1 to 2 weeks is enough to maintain protection.
Here are the natural deterrents that I suggest adding around your compost pile:
| Natural deterrent | How to use it |
| Peppermint | Rodents dislike the strong scent. Try planting mint nearby or using peppermint oil around the bin. |
| Garlic | Use crushed garlic or garlic spray to repel pests. |
| Hot pepper | Sprinkle cayenne or chili flakes around the compost to deter rodents. |
| Vinegar | A bowl of vinegar near the pile may help keep flies and some pests away. |
| Diatomaceous earth | Sprinkle around (not in) the compost pile. DE is an insect deterrent by dehydrating crawling pests like ants and roaches. |
| Predator urine products | Scents from natural predators like foxes or coyotes can trigger a fear response in small animals, making them less likely to approach the compost pile. These products are commercially available. |
| Citrus peels | Placed around the perimeter and in moderation can help repel rodents and other pests because of the strong citrus scent. |
Read more about natural deterrents:
Chop materials into small pieces
Breaking down materials before adding them to the compost speeds up decomposition and helps deter pests. By chopping fruit and vegetable scraps, tearing up leaves, and shredding paper or cardboard, you create a better environment for microorganisms to do their work. Aim for pieces about 1 to 2 inches in size for the best results.
Using the right tools makes the job easier:
- Kitchen scissors: They are great for soft food scraps.
- Garden shears: To cut tougher plant stems or woody materials. Cutting these in smaller pieces prevents air pockets, which can slow down decomposition and create hidden nesting spots for pests.
- Lawn mower: For large amounts of leaves.
Smaller pieces also help the pile heat up evenly. A heated pile breaks down faster and is less likely to smell or attract unwanted visitors.
Read more: 10 Best Lawn Mowers
Monitor for pests
Ultimately, the foolproof method to prevent infestations is to inspect your compost pile for signs of pests. Do it at least once a week, especially during warmer months when pest activity is higher. Here are some straightforward steps to keep an eye on:
- Check the surface: Inspect the surface of your compost. If you have a bin, pay close attention to any type of damage.
- Smell test: Healthy compost has an earthy smell. If your pile is smelling bad, it could signal that is too wet.
- Watch for tracks: If you believe rodents or wildlife are digging through your compost, look for small tracks or burrow marks around the bin.
In case you notice pest activity do the following:
| Pest | What to do |
| Rodents | Ensure wire mesh barriers are no larger than ¼ inch, cover food scraps with at least 2 to 3 inches of browns, and turn the pile weekly to disturb nesting. If they persist, consider switching to a sealed compost tumbler. |
| Insects | Flies are drawn to exposed food scraps, so always bury them under browns. If ants are present, the pile may be too dry, add moisture gradually and do the squeeze test. |
| Wildlife | Avoid composting meat, dairy, and greasy food, and secure your bin with a tight-fitting lid. |
Why do pests invade compost piles?
Pests invade compost piles because they see compost soil as an easy place to find food, shelter, and warmth. If the pile contains meat, dairy, or greasy leftovers, don’t be surprised if rodents, flies, and other critters appear.
A neglected pile, one that’s too wet, starts to smell, or isn’t turned often, only makes things worse, creating the perfect spot for pests to nest and multiply.
“A compost pile is an active ecosystem that is based on the breakdown of the organic materials that you are composting,” explains Ashley Andrews, an extension specialist at the College of Agriculture, Biotechnology & Natural Resources. “While a healthy compost pile ecosystem will help break down the compost into beautiful soil, compost can create a source habitat for garden pests or annoying insects that can ruin your barbeque.”
Common compost pile pests
Many pests view compost piles as an easy source of shelter and food. Rodents, raccoons, and opossums sift through scraps for meals, while flies and cockroaches are drawn to damp, decaying matter to lay their eggs. While some creatures are welcome in your compost pile, many others should be kept out.
Flies and insects
The first time I saw flies and insects in my compost pile, I panicked, thinking I had messed everything up. However, I soon realized that most of these insects are actually helpful.
“Most of the critters that gardeners see when they peer into their compost piles need to be there in order for compost to happen,” explains Merritt Melancon, an extension specialist at the University of Georgia Extension. “Earthworms, white worms, sow bugs, pill bugs, millipedes, snails, slugs, and mites all help break down the organic matter in the compost pile.”
That said, some insects, are a sign that something’s off in your compost. If you spot lots of ants, your pile is probably too dry. On the other hand, roaches, fly larvae, and swarms of flies usually mean there’s too much moisture. While they won’t ruin your compost, they can be a nuisance.
Rats and mice
Rats and mice love compost piles because they provide food, warmth, and a place to nest. Meat, dairy, and greasy scraps are tempting, but even an open or poorly managed pile can attract them.
The problem is, they won’t just stay in your compost. Once they’re around, they can find their way into your home, searching for more food and shelter. Even worse, rats can spread diseases to humans and pets through their droppings and urine.
Wildlife
Wildlife like raccoons, skunks, opossums, hedgehogs, grass snakes, and even bears see compost piles as an easy way to obtain food. Most of these animals have a sharp sense of smell and will dig through compost for scraps like meat, dairy, greasy foods, and grubs.
Troubleshooting common pest problems
If you’re dealing with bad odors, rats and mice near the compost, too many flies, or even signs of wildlife despite wrapping your compost bin in wire mesh, you’re not alone. These are some common issues. Let’s take a look at some of these challenges and how to correct them.
| Problem | Solution |
| Bad odor: If your compost smells bad, the main culprit is that it’s too wet and lacks oxygen. | Add more browns like dry leaves or shredded newspaper to absorb excess moisture. Turn the pile once a week to introduce oxygen and promote aerobic decomposition. |
| Lots of flying insects: This could happen because food scraps are exposed on top of the pile or if the pile is too wet and breaking down slowly. | Bury any green material under 2 to 3 inches of browns. If the problem persists, cover the pile with a breathable lid or tarp to discourage insects while still allowing airflow. |
| Rodents are invading: If rats and mice are still nesting in your compost bin despite wrapping it in wire mesh, your mesh holes are too big. | Make sure that the wire mesh is no wider than ¼ inch. Also, avoid composting bread, grains, or nuts, as these can attract rodents. |
| Ant infestation: Ants appear when compost is too dry. | Add moisture by sprinkling water or adding more greens to the pile and turning it. To check moisture, grab a handful of compost and squeeze it. It should be damp but not dripping. |
| Wildlife disturbances: If raccoons, opossums, or bears rummage through your compost, they may be drawn to strong-smelling food scraps. | Avoid composting meat, dairy, and greasy food, as these odors appeal to wildlife. Secure the bin with a tightly fitting lid. |
FAQs about keeping pests out of your compost
Yes, compost piles host many beneficial bugs that help to break down organic matter into nutrient-rich compost. Earthworms, centipedes, and mites feed on the compost material, improve aeration, and support microbial activity.
Yes, there are several ways to get rid of pests that have invaded your compost pile. First, you must adjust your compost maintenance routine like turning the pile once a week, adjusting moisture, covering food scraps with browns, and wrapping your bin with wire mesh or hardware cloth. If the problem persists, contact a pest control professional to help you eliminate the pests.
The most common pests in compost piles are fruit flies. They like moisture and food scraps. Fruit flies lay their eggs in the compost, and their larvae feed on decaying organic material. They are not harmful to the compost, but they can become a nuisance.
Find a pest control professional near you
Managing pests in your compost can be frustrating, but in most cases, it just takes a few simple adjustments to get things back on track. If you need help keeping your lawn healthy, mowed, cleaned, and pest-free, contact a Lawn Love professional in your area who can simplify the process.
Sources
- “Compost pile health can be judged by the company it keeps.” Published by Merrit Melancon. University of Georgia Extension.
- “The Ecosystem of Compost Piles.” Published by Ashley Andrews. University of Nevada, Reno Experiment Station.
- “Keeping Wildlife Away From Your Compost.” By Extension Master Gardener Nadie VanZandt. University of Vermont.
Main Photo Credit: Niwrat | Wikimedia Commons | CC BY-SA 4.0
