The most effective way to get rid of grasshoppers in your garden is to target them early, while they’re still small nymphs concentrated near where they hatched. Grasshoppers become harder to control as they grow and spread, so timing matters more than which method you choose. A combination of physical barriers, biological controls, and habitat management will give you the best results.
Why Timing Is Everything
Grasshoppers go through three life stages: egg, nymph, and adult. Nymphs pass through five development stages over about five to six weeks before reaching adulthood. The critical window for control is during the third and fourth stages, when they’re roughly half an inch to three-quarters of an inch long. In most regions, this falls in mid to late June.
At that size, most eggs have already hatched, the young grasshoppers are still clustered near their hatching areas, and they’re far more vulnerable to both biological and chemical treatments. Once they reach the fifth nymph stage or adulthood, their mobility increases dramatically and treatments become much less effective. If you wait until you see large grasshoppers chewing through your tomatoes in August, you’ve already missed the best opportunity.
How Many Grasshoppers Justify Action
Not every grasshopper sighting calls for intervention. University extension guidelines use density thresholds to determine when treatment makes sense. If you’re counting fewer than 2 grasshoppers per square yard in your garden beds, treatment isn’t necessary. At 3 to 7 per square yard, the decision depends on what you’re growing and how much damage you’re willing to tolerate. At 8 to 14 per square yard, treatment is probably worthwhile. Above 15 per square yard, action is clearly needed.
To estimate density, pick a few spots in your garden and slowly walk through a square-yard area, counting the grasshoppers that jump. Do this in the morning when they’re less active for a more accurate count.
Physical Barriers That Actually Work
Row covers are one of the most reliable ways to protect garden plants from grasshoppers without chemicals. Lightweight woven mesh draped over hoop structures keeps grasshoppers off your crops entirely. Choose a mesh grade small enough that grasshoppers can’t squeeze through. Install covers before grasshoppers arrive in your garden, not after you spot damage.
You can use PVC, metal, or wire hoops as a frame, then lay the mesh over the top and secure it with binder clips. The key is covering the crop completely on all sides, with edges pinned down using soil or heavy rocks placed every 3 feet along each side. Leave extra room inside for plant growth. One downside: weeds thrive under row covers, so you’ll need to periodically pull back the fabric to weed by hand or lay a weed barrier underneath.
Biological Controls for Long-Term Reduction
A naturally occurring grasshopper pathogen, sold as NOLO Bait or Semaspore Bait, offers a targeted biological approach. These products contain spores of a microorganism that infects grasshoppers when they eat treated bran bait. It stunts their growth and gradually kills them, and infected grasshoppers spread the pathogen to others through cannibalism (a common grasshopper behavior).
The catch is timing. Biological bait only works when applied against small nymphs in the third to fourth development stage, in or near their hatching areas. It also needs to be reapplied after rain or sprinkler irrigation, since moisture breaks down the bait. This approach is selective, killing only grasshoppers and other insects that eat the bait, which makes it a good fit for gardens where you want to protect pollinators and beneficial insects. Note that some biological bait products are not labeled for use on edible plants, so check the product label before applying near food crops.
Neem Oil as a Growth Disruptor
Neem oil works differently from conventional pesticides. Rather than killing grasshoppers on contact, it disrupts their growth and deters feeding. A neem oil spray can slow development enough to reduce damage, especially on younger grasshoppers. Mix about 3 teaspoons of pure neem oil into two quarts of warm water with half a teaspoon of mild liquid soap (castile soap works well), pour it into a spray bottle, and apply it to both plants and surrounding soil. You’ll need to reapply regularly since neem breaks down in sunlight.
Encouraging Natural Predators
Grasshoppers are a primary food source for birds, small mammals, lizards, and predatory insects. Building up predator populations around your garden can reduce grasshopper numbers by 50 percent or more over time.
Bluebirds, sparrows, wrens, flycatchers, and wild turkeys all eat grasshoppers readily. Installing bluebird boxes and creating brush piles for sparrows and wrens near your garden gives these birds nesting habitat close to your pest problem. Keeping the area around your garden mowed short makes it easier for birds to spot and catch grasshoppers in the open.
If you have the space and local regulations allow it, poultry is remarkably effective. Chickens, guinea fowl, and ducks all forage aggressively on grasshoppers. Guinea fowl are especially enthusiastic about it. Ranging poultry through or around the garden during grasshopper season provides daily, ongoing pest pressure that no single spray application can match.
Chemical Options for Severe Infestations
When grasshopper numbers are high and other methods aren’t enough, insecticide sprays and baits can knock populations down quickly. The main approaches break down into three categories.
- Insecticidal baits (wheat bran mixed with an insecticide) are spread evenly through the garden. Grasshoppers eat the bait while foraging. Baits are easy to apply and selectively target foraging insects, but they’re expensive and need to be reapplied after rain.
- Dust formulations are easy to apply but don’t stick well to leaves and also require frequent reapplication.
- Spray insecticides are the least expensive option. They adhere to plant surfaces and kill grasshoppers both on contact and when they eat treated foliage. Common active ingredients available in garden-center products include permethrin and carbaryl (sold under the Sevin brand, among others).
All chemical treatments work best against smaller, younger grasshoppers. Spraying adults that are already flying around your garden will provide some short-term relief, but new adults can keep arriving from surrounding areas. For this reason, neighborhood-wide coordination in spring, while grasshoppers are still nymphs, is far more effective than any individual garden treatment later in the season.
Cultural Practices That Reduce Populations
Grasshoppers prefer to lay eggs in undisturbed soil with sparse vegetation, particularly along field edges, roadsides, and weedy borders. Keeping the perimeter around your garden mowed and free of tall weeds removes both egg-laying habitat and the food sources that attract nymphs before they migrate into your beds.
Tilling garden soil in fall or early spring can expose and destroy grasshopper eggs before they hatch. Since eggs are laid in the top few inches of soil, even shallow cultivation disrupts egg pods. Combining this with row covers on your most valuable crops and biological bait applied to nymphs in early summer creates a layered defense that addresses grasshoppers at every stage of their life cycle.