How to Keep Mice Out of Your Garage

It doesn't matter whether your garage is neatly organized or a scene straight out of a hoarding show, garages are one of the easiest entry points for mice into your home. Garage doors get left open for stretches at a time whenever you're home, and that's plenty of opportunity for a mouse to slip in. Once mice are living in your garage, they're already halfway into your house, since a garage is usually just one wall away from your kitchen or basement. The good news is that a mouse-free garage is entirely achievable. It just takes making the space unappealing to them from every angle: food, shelter, and nesting material all at once.

Why Do Mice Hide in Garages?

When mice wander into your garage, they're looking for a few specific things: food, shelter, and nesting material, and most garages happen to offer all three at once.

Garages are typically where households store garbage, birdseed, and other animal food, which is exactly what draws mice in. Store all food and seed in plastic or metal containers with tight-fitting lids rather than the paper or cardboard packaging they usually come in.

What Are Signs of a Mouse Infestation?

Mice are fast and typically stay out of sight before you get a chance to actually see one. Cornell's New York State IPM Program notes that rodents use droppings to communicate about resources, which is part of why an infestation tends to grow quietly before it becomes obvious. A few signs worth checking for:

• Small, dark droppings, often near food containers or along walls
• Chewed-up paper, cardboard, or insulation
• Strange scratching or scurrying noises, especially at night
• Dark rub marks along the base of your garage walls
• Shredded nesting material tucked into corners or storage boxes

Mouse-Proof Your Garage

A garage functions a lot like a garden shed: plenty of places to hide, build a nest, and breed without anyone noticing. The most effective approach combines a few simple, preventative habits rather than relying on just one fix.

1. Seal Off Entry Points

Sealing off gaps and crevices around your garage is one of the most important things you can do to prevent a mouse problem, and it has to be done carefully. Cornell Cooperative Extension of Warren County notes that an adult mouse can squeeze through an opening as small as three eighths inch, which is roughly the width of a pencil.

• Make sure windows are closed and sealed properly
• Check that all doors shut snugly with no visible gaps
• Confirm the garage door closes fully and is sealed at the bottom

Cornell Cooperative Extension of Rockland County recommends a simple, low-cost fix for most gaps: caulk any entrance holes or fill them with putty or steel wool, paying close attention to where utilities enter the garage and around windows and doorways.

2. Remove Cardboard

Cardboard and other paper products are an easy nesting material for mice, so clearing it out removes one of the main reasons they'd want to stick around. Swap cardboard boxes for plastic storage containers with lids wherever you can. It denies mice a ready-made nesting source and makes your garage considerably less appealing.

3. Remove Clutter

Clutter is a rodent's best friend, mainly because it gives them somewhere to hide undisturbed. A bit of spring cleaning goes a long way here: clear anything piled on the floor, and move stored items up onto shelves instead of leaving them in stacks where mice can nest in peace.

4. Try Natural Repellents

If you've already sealed entry points and cleared out clutter but mice are still finding a way in, a few natural repellents can help as an added layer. Certain scents and textures irritate a mouse's senses enough to keep them at a distance:

• Peppermint oil: soak cotton balls in peppermint oil and place them wherever you've noticed mouse activity. The scent fades over a few days, so plan to refresh it.
• Cayenne pepper, black pepper, or cloves: make small pouches out of cheesecloth filled with any of these spices and tuck them into areas mice might be hiding.
• Used kitty litter: mice tend to associate the scent of cat urine with a predator nearby. Placing containers of used litter in problem areas can help keep them away.
• Electronic repellents: plug-in devices that emit a frequency mice dislike. They can help short-term, but mice often adjust to the noise over time, so don't rely on this alone.

5. When to Call a Professional

Prevention habits handle most garage mouse problems well on their own. They fall short once a population is already established.

If you've tried sealing entry points, clearing clutter, and using repellents but mice are still finding a way in, it's time to bring in professional rodent control before the problem moves from your garage into the rest of your home.

At A&C Pest Management, we've been a family-owned and operated business serving Long Island for over 57 years. If you've tried everything and mice are still finding their way into your garage, reach out to our team and we'll take it from here.