Yes, grasshoppers will eat tomato plants, and they can cause real damage

Grasshoppers eat tomato leaves, stems, and sometimes the fruit itself. They chew irregular holes in the foliage and can strip entire sections of a plant bare if the population is large enough. A few grasshoppers on your plants are usually not a problem, but during years when grasshoppers are abundant in your area, they can move through a garden and cause noticeable damage in days.

The damage looks different from other pests: grasshoppers leave ragged, uneven holes rather than the clean round holes made by beetles, and they do not leave the sticky residue or webbing that some other insects do. If you see this pattern of damage and spot grasshoppers on or near your plants, they are likely the culprit.

Key Takeaways

  • Grasshoppers chew irregular holes in tomato leaves and can strip plants bare during population peaks, though light feeding usually does not harm the plant.
  • Damage is worst in mid to late summer when grasshopper populations are largest, and in dry years when grasshoppers thrive.
  • Netting, row covers, and removing nearby weeds and tall grass reduce grasshopper pressure without chemicals.
  • Insecticidal soap and spinosad are low-toxicity options if grasshopper populations become severe; neem oil is less effective on grasshoppers than on other pests.

When grasshoppers are most likely to damage your tomatoes

Grasshopper damage peaks in mid to late summer, usually July through September in most of North America. This is when grasshoppers reach their adult size and eat the most. Nymphs (young grasshoppers) feed earlier in the season but cause less visible damage because they are smaller.

Dry years bring heavier grasshopper populations. Grasshoppers thrive in hot, dry conditions and struggle in wet springs and summers. If your region has had little rain and warm temperatures, watch your tomatoes more closely. Grasshoppers also move into gardens when the surrounding landscape is mowed or dried out—they migrate toward green plants when their natural habitat disappears.

How to tell grasshopper damage apart from other pests

Grasshoppers leave ragged, irregular holes with torn edges. The damage is random across the leaf rather than following a pattern. You will often see the grasshopper itself on or near the plant, especially in early morning or late afternoon when they are most active.

Other pests leave different signatures: Japanese beetles cut clean, round holes; spider mites create fine stippling or yellowing; caterpillars often leave droppings and may web leaves together. If you see a grasshopper on the plant and ragged holes nearby, grasshoppers are the problem.

Physical barriers that stop grasshoppers before they feed

Row covers (lightweight fabric laid over plants and anchored at the edges) block grasshoppers completely. Use them when plants are young and remove them once flowers appear so pollinators can reach the blooms. Netting with a mesh smaller than 1/4 inch also works, though grasshoppers can sometimes push through larger mesh.

These barriers work best as prevention—install them early in the season before grasshoppers arrive. Once grasshoppers are already feeding, removing and replacing covers can crush insects and damage plants. If you use covers, check underneath regularly for grasshoppers that may have been trapped inside.

Removing habitat that attracts grasshoppers to your garden

Grasshoppers hide and lay eggs in tall grass, weeds, and plant debris. Mow or trim grass and weeds within 20 feet of your garden if possible. Remove dead plant material and keep the area around your tomatoes clear of clutter where grasshoppers can shelter.

This approach takes time to show results but reduces the grasshopper population near your plants over the season. It also makes your garden less attractive to grasshoppers migrating from dried-out areas. Combine habitat removal with other methods for better control.

Insecticidal soap and spinosad for heavier infestations

Insecticidal soap kills grasshoppers on contact by breaking down their outer coating. Spray it directly onto grasshoppers and affected foliage in early morning or late afternoon. It works best on nymphs and smaller grasshoppers; large adults are harder to kill. Reapply every 7 to 10 days if grasshoppers return.

Spinosad is a naturally derived insecticide that grasshoppers ingest when they feed. It works more slowly than soap but continues working after process. Follow label directions for timing and reapplication. Both products break down quickly in sunlight and rain, so timing matters.

Neem oil is sometimes recommended for grasshoppers but is less effective than it is for other pests. Grasshoppers do not feed as readily on oily leaves, and the oil does not kill them as reliably as soap or spinosad does.

When grasshopper damage is not worth treating

Light feeding—a few holes on a few leaves—does not harm tomato plants or reduce your harvest. Tomato plants are vigorous and can tolerate some leaf damage. If grasshoppers are present but damage is minor, you can leave them alone and monitor the plants.

Treatment becomes worth considering when grasshoppers are stripping leaves faster than the plant can replace them, or when damage is spreading to new plants daily. At that point, the cost and effort of treatment is less than the cost of losing plants or a significant portion of your harvest.

Frequently Asked Questions

Can grasshoppers damage tomato fruit directly?

Yes, but it is less common. Grasshoppers usually prefer leaves and stems because they are softer and easier to chew. They will eat ripe or ripening fruit if leaf damage is severe and food is scarce, leaving irregular gouges in the skin. Green fruit is rarely damaged.

Will grasshoppers kill a young tomato plant?

A heavy population can strip a young plant bare and stunt or kill it, especially seedlings. Mature plants tolerate more damage. Use row covers on young plants during peak grasshopper season, or plant later in the season when grasshopper populations are declining.

Do all grasshopper species eat tomatoes?

Most grasshoppers are plant-eaters and will feed on tomatoes if given the chance. A few species are carnivorous or prefer specific plants, but the common grasshoppers in gardens—including field grasshoppers and locusts—will eat tomato foliage.

Is it safe to eat tomatoes after spraying with insecticidal soap or spinosad?

Both products are considered low-toxicity and break down quickly. Follow label directions for the number of days to wait before harvest. Most labels allow harvest within 7 days for insecticidal soap and 1 to 3 days for spinosad, but always check your specific product.

Why do grasshoppers suddenly appear in large numbers some years?

Dry, warm weather favors grasshopper reproduction and survival. Wet springs kill eggs and nymphs. If your region has had several dry years in a row, grasshopper populations build up. They also migrate into gardens when surrounding fields are mowed or dried out.