The bugs eating your strawberries depend on the type of damage you’re seeing. Small holes in the fruit, misshapen berries, slimy trails, tiny webs on leaves, and foamy blobs on stems all point to different pests, each with a different fix. The good news is that most strawberry bugs can be managed without heavy pesticides, and some barely need treatment at all.
Identify the Bug by the Damage
Before you treat anything, figure out what you’re dealing with. The damage pattern on your fruit and leaves is the fastest way to narrow it down.
- Small holes or large chunks eaten from fruit: Sap beetles. These small, dark beetles bore into ripe or overripe berries, leaving visible holes in the bottom or devouring sections from the side.
- Misshapen, “cat-faced” berries: Tarnished plant bugs. Their nymphs puncture young fruit before it fully develops, so the damaged spots stay small while the rest of the berry grows around them.
- Slimy trails on fruit with ragged holes: Slugs. The easiest pest to confirm because they leave a visible mucus trail on the berry surface.
- Stippled, bronzed leaves with fine webbing underneath: Two-spotted spider mites. You may need a magnifying glass to see them, but the webbing between leaves and stems is a giveaway.
- Foamy white blobs on stems: Spittlebugs. The foam protects the nymph inside. They rarely cause serious damage unless they’re present in large numbers during dry weather.
- Notched leaf edges and stunted, dark plants: Root weevils. The adults chew leaf margins, but the real damage comes from larvae feeding underground on roots.
Getting Rid of Sap Beetles
Sap beetles are attracted to ripe and fermenting fruit, so the single most effective thing you can do is harvest frequently and remove any damaged, overripe, or rotting berries from the patch. Leaving even a few mushy berries on the ground is like setting out a welcome sign.
You can also trap sap beetles using simple bait stations placed a few feet outside your garden. Fill shallow containers with stale beer, a molasses-water-yeast mixture, vinegar, or pieces of overripe fruit. The idea is to lure them away from your plants. Empty and rebait the traps every three to four days so they stay effective and don’t become a breeding site themselves.
Managing Tarnished Plant Bugs
Tarnished plant bugs are one of the more frustrating strawberry pests because the damage doesn’t show up until harvest. The nymphs (small, pale green insects) feed on flowers and developing fruit, and by the time you see lopsided berries, the feeding already happened weeks earlier.
The threshold that signals a real problem is roughly one nymph per every two flower clusters. To check, tap open flower clusters over a white plate or sheet of paper and count what falls off. If you’re below that threshold, the damage is usually cosmetic and limited. Above it, an insecticide labeled for strawberries can help. Spinosad-based products are a common choice for home gardens and have a shorter waiting period before you can safely pick fruit, typically around 24 hours compared to several days for other options.
Slug Control
Slugs feed at night and thrive in moist conditions, which makes strawberry beds ideal habitat. Removing their hiding spots is the first step: clear mulch back slightly from the base of plants, pick up boards or debris near the patch, and improve air circulation so the soil surface dries out during the day.
Iron phosphate bait pellets, sold at most garden centers, are effective and safe to use around edible crops. Scatter them around the perimeter of your strawberry bed in the evening. You can also set out shallow dishes of beer as traps. Slugs crawl in and drown. Raised beds and copper tape around bed edges create physical barriers that slugs avoid, since copper reacts with their slime and creates an unpleasant sensation.
Controlling Spider Mites
Two-spotted spider mites explode in hot, dry weather. They’re nearly invisible to the naked eye, but their damage is obvious: leaves develop a speckled, bronze look, and fine silk webbing appears on the undersides. Left unchecked, heavy infestations reduce plant vigor, stunt growth, and can kill plants entirely.
A strong blast of water from a hose knocks mites off leaves and disrupts their webbing. Do this every few days, focusing on the undersides of leaves. For persistent infestations, predatory mites are one of the most reliable biological controls. Two species work well on strawberries: one is a specialist that aggressively hunts spider mites in warm, humid conditions, and the other is a generalist that tolerates a wider range of temperatures and stays active even when prey is scarce. You can order both from online insectary suppliers. Release them when you first notice mite damage rather than waiting for a full-blown infestation.
Avoid broad-spectrum insecticides for spider mites. These products kill the natural predators that keep mite populations in check, often making the problem worse within a few weeks.
Dealing With Spittlebugs
Those foamy spit-like masses on your strawberry stems look alarming but are usually harmless. Each blob hides a single nymph feeding on plant sap. In most years, spittlebugs cause little to no yield loss.
A strong stream of water from a garden hose washes the protective froth away, exposing the nymph to predators and drying it out. That’s typically all the control you need. Treatment only becomes necessary when spittlebugs are numerous and the weather is dry, since their feeding under those conditions can stunt fruit and reduce yields.
Root Weevil Larvae
Root weevils are a two-part problem. Adults feed on leaves at night, leaving distinctive notches along the edges, but this cosmetic damage isn’t a concern. The real threat is underground, where C-shaped white larvae feed on roots through fall and winter, causing stunted, dark plants with bunched-up leaves.
Beneficial nematodes, microscopic worm-like organisms that parasitize soil-dwelling larvae, are the most effective organic control. Apply them in late summer or early fall, when larvae are actively feeding near the soil surface. The soil needs to be thoroughly wet and warmer than about 53°F for the nematodes to survive and find their targets. Water the bed heavily before and after application. You can find beneficial nematodes at well-stocked garden centers or through mail-order suppliers.
Preventing Bugs Before They Arrive
Most strawberry pest problems get worse when conditions favor the insects over the plants. A few preventive habits make a noticeable difference season over season.
Keep the patch clean. Remove old leaves, spent fruit, and plant debris regularly. This eliminates hiding spots for slugs, overwintering sites for weevils, and fermenting fruit that attracts sap beetles. Renovate June-bearing beds after harvest by mowing the foliage and thinning runners so plants have good airflow.
Companion planting can also help. Borage planted among strawberries strengthens the plants’ resistance to insects and disease, and strawberry growers have long tucked a few borage plants into their beds for this reason. Thyme planted as a border helps deter certain worms and caterpillars. Onions interplanted with strawberries support disease resistance. Avoid planting strawberries near cabbage-family crops like broccoli, Brussels sprouts, and cauliflower, which can attract shared pests.
Row covers made of lightweight fabric placed over plants during bloom can physically exclude tarnished plant bugs and other flying insects. Remove covers during the day if you need pollinator access, or use them selectively during the period when tarnished plant bug nymphs are most active in spring.
If you do use a pesticide, check the label for the pre-harvest interval, which tells you how many days you must wait between spraying and picking. For strawberries, this is commonly three days for many residential products, though spinosad-based sprays can allow harvest within 24 hours. Always follow label directions, since strawberries are eaten fresh and often by children.