Earwigs on Marigolds: Problem or Pest?

Earwigs are nocturnal insects with distinctive pincers at their tail end. They hide in dark, moist crevices during the day — including inside flower heads — and feed at night. On marigolds, earwig damage appears as irregular holes in petals and leaves. The good news is that earwigs are also beneficial garden predators that eat aphids, mites, and other small pests, so the decision on whether to control them requires a little balance.

Identifying Earwig Damage on Marigolds

Look for ragged holes in petals and leaves with a slightly torn appearance (unlike the smooth, circular holes slug damage often shows). Check inside flower heads at night with a torch — earwigs favour the warm, sheltered environment of dense blooms like African marigolds. You will typically find brown, shiny insects up to 15 mm long with characteristic rear forceps. Small, scattered holes in otherwise healthy plants are usually not worth treating. Widespread petal destruction on display plants is the threshold for action.

Trap Pots — the Classic Method

Earwigs are easily trapped with a simple inverted flower pot stuffed with straw or shredded paper and placed on a cane near affected plants. Earwigs crawl in to shelter during the day. Check each morning and either destroy the contents or relocate the earwigs to a part of the garden where their aphid-eating habits are more welcome. Repeat nightly trapping for a week or two reduces local populations effectively without any chemical use.

Reduce Daytime Hiding Places

Earwig populations build up in gardens with plenty of debris — leaf litter, loose stones, wooden edging, and dense mulch all offer daytime refuge. Clearing unnecessary debris from around marigold beds reduces the habitat available to earwigs. Avoid leaving cut plant material on the soil surface around susceptible plants.

Night-Time Hand Collection

Going out after dark with a torch and collecting earwigs by hand into a jar of soapy water is time-consuming but very effective on a small scale. It is the least disruptive approach for a gardener who wants to remove earwigs from one specific bed without affecting the rest of the garden.

When Earwigs Are Actually Helpful

In beds with aphid pressure, earwigs are allies. If your marigolds have aphids alongside earwig damage, tolerate the earwigs — they will help control the aphid colony. In a garden with good ecological diversity, earwigs rarely reach densities that cause serious damage. Only intervene if display plants are being noticeably disfigured and you have no significant aphid problem that the earwigs are managing.