Stink bugs are one of the most common pests on tomato plants, and the damage they leave behind is distinctive: discolored spots on the fruit surface with spongy, white tissue underneath. Several species target tomatoes, and they can affect fruit at nearly every stage of ripening. The good news is that stink bug damage is manageable with a combination of physical removal, prevention strategies, and targeted treatments when populations get out of hand.
How Stink Bugs Damage Tomatoes
Stink bugs are piercing-sucking insects. They push a needle-like mouthpart into the fruit, inject digestive enzymes, and then suck out the liquefied tissue. This feeding creates a condition called “cloudy spot,” which looks different depending on when the bug feeds and how ripe the fruit is.
On green tomatoes, the damage appears as dark pinpricks surrounded by whitish areas with indistinct borders. Individual spots range from 1/16 to 1/2 inch across, but multiple feeding sites can merge into large discolored patches. As the fruit ripens, these spots turn golden yellow instead of red. If you peel back the skin over a feeding site, you’ll find a white, shiny, spongy mass of tissue that stays firm while the rest of the tomato softens normally.
Younger stink bugs (nymphs) leave their own signature mark: small yellow “starburst” patterns on red fruit, with a shallow pocket of spongy white tissue just beneath the surface. Beyond the cosmetic damage, stink bug feeding can introduce yeast and fungal pathogens into the fruit, especially in dense, humid plant canopies where moisture lingers.
Can You Eat Stink Bug-Damaged Tomatoes?
Tomatoes with cloudy spot are safe to eat. The spongy tissue under the feeding sites has an off texture and may taste bland or slightly bitter in that area, but it poses no health risk. You can cut away the damaged portions and use the rest of the fruit normally. For cooking, sauces, or canning, minor stink bug damage is barely noticeable once the tomato is processed.
Which Stink Bugs Attack Tomatoes
Four species cause most of the trouble on tomatoes in the United States. The brown marmorated stink bug is the most damaging and widespread. It’s an invasive species, about 5/8 inch long, mottled brown or gray, with alternating dark and pale bands along the edges of its abdomen. Look for a distinctive white band on each hind leg and white bands on the antennae.
The consperse stink bug is slightly smaller at about 1/2 inch, grayish brown to green, with grayish legs speckled in black. The southern green stink bug is bright green and roughly the same size. The Say stink bug is bluish green with a paler whitish margin along the body. All four are shield-shaped with a large triangular plate on their backs, which is the easiest way to identify any stink bug at a glance.
Stink bugs overwinter as adults under leaf litter, plant debris, and weedy areas. They emerge in spring and begin feeding on a wide range of fruits and vegetables. Females lay barrel-shaped eggs in clusters of 10 to 30 on the undersides of leaves. The eggs start white and darken as they mature. Nymphs hatch and initially feed close together, then scatter as they grow. They look like smaller, rounder versions of the adults with more colorful patterns in black, red, white, and green.
Handpicking and Physical Removal
For home gardeners, the simplest approach is picking stink bugs off your plants by hand and dropping them into a bucket of soapy water. The soap breaks the surface tension so the bugs sink and drown rather than crawling back out. This works best in the morning when stink bugs are sluggish. Check the undersides of leaves for egg clusters too. They’re easy to spot, and scraping them off before they hatch eliminates dozens of future nymphs at once.
This method takes patience but is highly effective in small gardens where you can inspect plants regularly. Stink bugs are slow movers and don’t bite, so there’s no real obstacle beyond the unpleasant smell they release when disturbed (hence the name).
Trap Crops and Prevention
Trap cropping is a proven strategy that takes advantage of stink bugs’ preference for certain plants. Sunflowers, sorghum, millet, and buckwheat all attract stink bugs more strongly than tomatoes. Planting these around the perimeter of your tomato patch creates a buffer zone that intercepts the bugs before they reach your crop.
A few guidelines make trap cropping more effective. Plant the trap crop 3 to 4 weeks before your tomatoes so it matures first, since stink bugs are drawn to whichever plant is further along. Keep the trap crop at least 5 feet from your tomato plants. Aim for a ratio of about 10 to 20% trap plants relative to your main crop. The critical step most people skip: once stink bugs have gathered on the trap crop, you need to remove or kill them there. Otherwise they’ll eventually wander over to your tomatoes anyway.
Good garden hygiene also helps. Clearing leaf litter, weeds, and plant debris in fall reduces overwintering habitat near your garden. Stink bugs shelter in these spots through winter and emerge ready to feed in spring, so cleaning up in autumn means fewer adults arriving when your tomatoes start setting fruit.
Natural Predators
The most effective natural enemy of the brown marmorated stink bug is a tiny parasitoid called the samurai wasp. These wasps are black, shiny, and barely visible at 1 to 2 millimeters long. They lay their eggs inside stink bug eggs, and the developing wasp kills the stink bug before it ever hatches. An adult wasp emerges from the parasitized egg after about 10 to 14 days.
In their native range in Asia, samurai wasps destroy up to 80% of stink bug eggs, typically attacking every egg in a cluster. These wasps have been found establishing naturally in parts of the U.S. and pose no risk to crops or people. You can encourage beneficial insects broadly by avoiding broad-spectrum insecticides and planting small-flowered herbs and wildflowers that provide nectar for parasitoid wasps and other predators.
When Spraying Makes Sense
In most home gardens, handpicking and trap cropping are sufficient. But if stink bug numbers are overwhelming your plants, insecticidal soap applied directly to the bugs can knock down populations without harming beneficial insects once it dries. Soap sprays only work on contact, so thorough coverage matters, and you’ll likely need repeat applications.
For larger plantings, the general threshold used by commercial growers is helpful as a reference: roughly one stink bug per two plants, on average, will result in about 5% of fruit showing damage. If you’re growing tomatoes for fresh eating and appearance matters, that level of damage may be worth treating. If you’re growing for sauce or canning, you can tolerate significantly more stink bug activity, since the damaged tissue is easily trimmed away.
Pyrethroid-based insecticides are effective against stink bugs but kill beneficial insects indiscriminately, including the parasitoid wasps that provide long-term control. If you go this route, apply in the evening when pollinators are less active, and treat only the areas of your garden where stink bugs are concentrated rather than spraying everything. Targeted application preserves the natural predators working in your favor elsewhere in the garden.
Timing Your Inspections
Start scouting your tomato plants once fruit reaches about one inch in diameter. That’s when stink bugs become interested. Check the fruit itself for the telltale pinprick marks and discolored halos, and look on leaves and stems for adults, nymphs, and egg masses. Stink bug populations tend to build through summer as new generations hatch, so damage often intensifies from midsummer through early fall. Regular weekly inspections let you catch problems before they escalate, and early-season egg removal can prevent the population boom that makes late-season control so difficult.