A grasshopper or two inside your house is usually a simple problem: they wandered in through an open door, a gap in a window screen, or a crack you haven’t noticed yet. The fastest fix is to physically catch and release them, then seal up the entry points so more don’t follow. If you’re dealing with repeated invasions, especially during late summer when grasshopper populations peak, you may need a combination of exclusion, repellents, and perimeter treatments to keep them out for good.
Catch and Remove Them First
Grasshoppers inside a house are disoriented. They’re looking for a way out, not trying to set up residence. That makes them relatively easy to catch if you’re patient. The simplest method is the cup-and-cardboard trick: place a glass or plastic container over the grasshopper, slide a piece of stiff paper or cardboard underneath, and carry it outside. Grasshoppers jump when startled, so approach slowly and from behind when possible.
If the grasshopper is on a wall or ceiling where a cup won’t work, try gently guiding it toward a window or door with a broom. Opening a nearby window with the lights off and a porch light on outside can also draw them out, since grasshoppers are attracted to light. For a grasshopper hiding behind furniture, moving the furniture slightly will usually send it hopping into the open where you can catch it.
Find and Seal Their Entry Points
Grasshoppers don’t need much space. Gaps as small as 1/16 of an inch can let insects into your home. The most common entry routes are gaps under doors, torn or poorly fitted window screens, cracks around window frames, and openings where pipes, wires, or vents pass through exterior walls.
Start with the basics: install door sweeps or thresholds at the base of every exterior door. Pay special attention to bottom corners, which are where insects most commonly slip through. If you have a garage door, fit it with a rubber bottom seal (vinyl seals tend to crack and fail in cold weather). For sliding glass doors, line the bottom track with half-inch to three-quarter-inch foam weatherstripping to close the gap underneath.
Next, inspect the perimeter of your home for less obvious openings. Seal cracks around windows, doors, and fascia boards with silicone or acrylic latex caulk. Plug utility openings where pipes and wires enter the foundation or siding, including around outdoor faucets, gas meters, dryer vents, and cable lines. Expandable foam, caulk, steel wool, or copper mesh all work for larger holes. Repair or replace any torn window screens, and make sure screens fit tightly in their frames with no gaps at the edges.
Natural Repellents for Doorways and Windows
If grasshoppers keep finding their way in despite your sealing efforts, natural repellents around entry points can add another layer of defense. Neem oil is one of the more effective options. It disrupts grasshopper feeding and development, making treated areas unappealing. Mix two quarts of warm water with half a teaspoon of mild liquid soap like castile soap, then slowly stir in three teaspoons of pure neem oil. Pour it into a spray bottle and apply around doorframes, windowsills, and any cracks you can’t fully seal.
Garlic spray and hot pepper spray are also popular among gardeners for deterring grasshoppers. These won’t kill them, but the strong smell and taste discourage them from lingering. You can make garlic spray by blending several cloves with water, straining it, and spraying it around entry points. These natural options break down quickly, so reapply every few days or after rain if you’re using them outdoors.
Diatomaceous earth, the food-grade kind, can be sprinkled along windowsills, door thresholds, and gaps in baseboards. It works by damaging the waxy coating on an insect’s body, causing dehydration. It’s nontoxic to humans and pets but needs to stay dry to remain effective.
Perimeter Treatments for Persistent Problems
When natural methods aren’t enough, a perimeter spray around the outside of your home can stop grasshoppers before they reach your doors and windows. Products containing permethrin or bifenthrin are commonly used for outdoor perimeter treatment. These are contact insecticides, meaning grasshoppers are killed when they walk across or land on treated surfaces. Spray a band along the base of your home’s exterior walls, around window frames, and near doorways.
For yard-level control, granular baits made with wheat bran are effective because grasshoppers actively eat them while foraging. These baits need to be spread evenly across the area where grasshoppers are congregating. The downside is they must be reapplied after rain or sprinkler irrigation, since moisture breaks them down quickly.
If you’re catching grasshoppers early in the season when they’re still small (roughly a quarter to half an inch long), a biological bait containing a natural grasshopper pathogen can reduce the local population over time. This pathogen is selective to grasshoppers and doesn’t harm other insects, but it only works on young nymphs. By the time grasshoppers are full-sized adults jumping into your house, this option is no longer effective for the current generation.
Keeping Pets and Children Safe
If you use any insecticide, whether sprays, dusts, or baits, take precautions before applying. Remove pets, pet toys, food bowls, water dishes, and bedding from the treatment area. Keep pets and children away from treated surfaces until the product has dried completely or for whatever time the label specifies, whichever is longer. For granular products applied outdoors, this waiting period can be 24 hours or more since the granules need to dissolve before they’re considered settled.
Baits pose a particular risk because they’re designed to be appetizing to insects, and many pets find them equally interesting. Place any bait stations in locations pets can’t reach, or use tamper-resistant bait stations. If you use indoor foggers for any reason, remove all animals from the house, cover fish tanks, and turn off central air systems that could circulate the pesticide through your home. Make sure the area is well ventilated during drying to reduce residue exposure when pets return.
For the lowest-risk approach overall, stick with physical removal, sealing entry points, and natural deterrents like diatomaceous earth and neem oil. These methods handle most indoor grasshopper problems without introducing chemicals into your living space.
Why Grasshoppers Come Inside
Understanding the pattern helps you prevent it. Grasshoppers are most active from midsummer through early fall, and populations spike in hot, dry years when their eggs survive winter in greater numbers. They’re drawn to artificial light at night, which is why you’ll often find them near porch lights, illuminated windows, and open garage doors in the evening. Switching outdoor lights to yellow “bug lights” or turning off unnecessary exterior lighting during peak season can noticeably reduce how many end up at your doorstep.
Grasshoppers also move toward buildings when surrounding vegetation dries out or gets mowed, since they’re looking for food and moisture. Keeping a buffer of taller vegetation or gravel between your lawn and your home’s foundation can reduce the number that wander close enough to find a way in. If your yard borders open fields or rangeland, you’re more likely to deal with large numbers, and perimeter treatments become more practical than trying to catch them one at a time.