5 Easy Bug Trapping Techniques for Autumn (Your Future Garden Will Thank You!)

The tail end of the season may seem to be an unlikely time for trapping insect pests, but it’s actually an opportune time to reduce future problems with several common garden enemies like slugs, fruit flies and earwigs. Thoughtful trapping also can help manage insects that invade indoor spaces later in the season such as fruit flies and fungus gnats. Here are five easy trapping techniques to try in the autumn.

1. Bread Dough Slug Traps

My last lettuce planting is riddled with slugs, but having them in one place provides an easy shot at productive trapping. As explained in more detail here, the most effective slug traps in this situation are deep pit traps made from plastic food containers, which are baited with a simple mixture of flour, water, and baking yeast. Often called bread dough slug traps, they attract slugs with fermentation gases, and then they fall in and can’t get out. Bread dough slug traps work best when placed among infested plants or inside the corners of raised beds for a few days. Slugs that are trapped in autumn won’t be waiting to feast on your tender seedlings first thing in spring.

2. Fleece Earwig Traps

Raised beds are great for plants and gardeners, but in rainy years the inner edges of framed beds and planters become havens for irritating earwigs, which feed on plants at night. When the weather gets too wet, they climb upward to escape soggy conditions. After seeing them congregate in the folds of horticultural fleece I was using over beds and in pieces piled on the ground, I started making earwig traps from fleece scraps draped over stakes and loosely secured with rubber bands. When it rains, the earwigs crawl up inside the ghost-like tents. Successful traps can be quickly gathered up and shaken out in a distant part of the yard.

In container gardens or greenhouses, you will still want to use shallow containers baited with cooking oil laced with soy sauce to trap earwigs. Or, set out habitat traps made from cloth, which is a good way to trap them on decks and patios. Earwigs naturally gather in family groups, and they feel quite safe under folds of damp cloth. Lightly dampen a stained old tea towel, roll it into a loose roll, and place it in a spot where earwigs are known to gather. Shake out captives into a pail of very soapy water.

3. Easy Fruit Fly Traps

Let’s say an apple core gets dropped into a seldom-emptied waste can, and the next thing you know your kitchen is abuzz with fruit flies. An abundance of fruit bits in the compost pail can make problems worse, but stepping up sanitation and using traps baited with fermenting fruit or vinegar can put a prompt end to fruit fly problems. A few drops of dishwashing liquid make fruit fly traps more effective. Partially covering the tops or using narrow-necked bottles prevents escapees.

4. Sticky Traps for Fungus Gnats

I often use gel stickers to keep winter birds from crashing into our windows, changing them out with the holidays. By accident, I discovered that after a few weeks’ time, the stickers often became death traps for fungus gnats, which often come indoors along with plants that spent the summer on the deck.

Fungus gnats are not particularly fond of the stickers, but they are so tiny that they become ensnared by the gel from casual encounters. Fungus gnats are attracted to plants grown under lights, where they are easy to snare in yellow sticky traps. You don’t need heavy-duty adhesives. A piece of yellow paper or plastic glued to a craft stick and striped with two-sided tape works just fine.

Bugs, Beneficial Insects and Plant Diseases

Slug Guide

Earwig Guide

Fungus Gnat Guide