What Do Stink Bugs Eat?

Stink bugs are plant eaters. They pierce fruit, vegetables, leaves and stems with a needle-like mouthpart and suck out the juices. They do not eat fabric, wood, food in your cupboards, or people — which is why finding them indoors is annoying rather than damaging.

What they feed on:

• Fruit — apples, peaches, pears, berries, tomatoes, citrus
• Vegetables — peppers, beans, sweetcorn, okra, cucumbers
• Field crops — soybeans, maize, cotton
• Ornamental plants and tree leaves, seeds and stems

The brown marmorated stink bug, the species most people encounter in homes, is an invasive pest from East Asia and feeds on more than 100 plant species. That range is why it causes serious agricultural losses.

A few species are predatory. The spined soldier bug and similar species hunt caterpillars, beetle larvae and other soft-bodied insects, making them genuinely beneficial in a garden. So not every stink bug is a pest, though the ones getting into your house almost certainly are.

What they do to plants: feeding leaves dimpled, scarred or corky patches on fruit — often called "cat facing" on tomatoes and peaches. The fruit is still safe to eat once cut around, but it's unsellable, which is the real cost.

Do stink bugs bite? No. Their mouthparts are built to pierce plant tissue, not skin. They can't bite or sting you, and they don't carry disease. Very rarely one may probe at skin, which can feel like a pinprick, but they aren't feeding on you.

Are they dangerous or poisonous? No. They're harmless to people and pets. The defensive fluid can irritate eyes or sensitive skin, so wash your hands after handling one. Dogs or cats that eat one may drool or vomit from the taste, but it isn't toxic.

Do stink bugs fly? Yes. They have wings under the hard shield-shaped back and fly clumsily and noisily, which is often how people notice them — a heavy, blundering flight into a lamp or window.

What do they smell like? The odour is often described as coriander, burnt rubber, or rotten almonds, and comes from chemicals released from glands on the thorax when they're threatened or crushed. It's a defence against predators, and it lingers on hands and surfaces.

Why they come indoors. They aren't looking for food in your house — they're looking for somewhere to overwinter. As temperatures drop in autumn they seek sheltered spaces, entering through:

• Gaps around windows and doors
• Cracks in siding and around utility pipes
• Attic and soffit vents
• Damaged window screens

They're drawn to warm, sunny walls — south and west-facing sides of buildings get the most. They're also attracted to light at night.

How to get rid of stink bugs:

• Vacuum them up. The most effective removal method, but use a vacuum with a bag you can throw away immediately, or a dedicated shop vac, because the smell will linger in the machine otherwise.
• Don't squash them. Crushing releases the odour and, according to some research, may attract more of them.
• Soapy water trap. Knock them into a bowl of water with a squirt of dish soap; they sink and drown quickly.
• Light trap. A lamp over a pan of soapy water in a dark room is effective overnight.
• Seal entry points. Caulk gaps, repair screens, fit door sweeps and cover vents. This is the only thing that solves the problem long-term.
• Sweep them outside with a broom and dustpan if there are only a few.

What kills them: soapy water, a mix of hot water and dish soap sprayed directly, and diatomaceous earth around entry points. Insecticides indoors are generally not worth it — they kill bugs inside walls where you can't remove them, and the bodies attract carpet beetles.

Prevention before autumn: seal cracks in late summer, before they start looking for shelter. Once they're in the walls, they're extremely hard to remove, and they'll reappear on warm winter days when they wake up and wander into living spaces.

How long do they live? Adults typically live 6 to 8 months, and those overwintering indoors survive the whole winter in a dormant state before emerging in spring.

Do they reproduce indoors? Generally no. They don't breed inside houses — they're only sheltering, and lay eggs on plants outdoors in spring. So an infestation doesn't multiply while it's in your attic.