Vermicomposting Pests: Preventing Fruit Flies In Worm Bins

Vermicomposting Worm Bin
worm bin
(Image credit: Courtney Bennett)

Worm bins are one of the best gifts any gardener can give themselves, even though they require a fair amount of attention. When worms eat your garbage and turn it into incredibly rich, black castings, there's lots to celebrate, but even the best worm system is prone to vermicomposting pests. Fruit flies in vermicompost are an annoying problem but, thankfully, they're not among the more serious pests you'll encounter during your adventures in worm farming. A few changes in your worm routine should send any accumulating flies packing.

How to Prevent Fruit Flies

Preventing fruit flies in worm bins is a difficult challenge; most vermicomposters find they simply have to learn to manage these insects. Because fruit flies and worms have very similar needs, it can be a delicate dance adjusting your worm bin to conditions that will completely eliminate or prevent fruit flies. Here are a few tricks that work well to keep fruit fly populations away from your vermicompost for longer: Feed your worms non-rotten food that's cut into small pieces. The smaller sized chunks are easier for worms to eat completely before the food begins to decompose and attract flies. Rotten food is a great host for fruit fly larvae, so avoid adding more pests to the pile by feeding only still-edible choices. Don't overfeed your worms. For the same reason that rotten food or food cut in too large of chunks is an attractant, overfeeding brings mature flies to the vermicompost bin. Feed a little bit at a time, waiting until your worms have eaten all the food before adding more. Conceal food items. Make sure to bury your food items and cover the top of the material inside the worm bin with a loose sheet of newspaper. These extra precautions help to prevent fruit flies from ever getting a whiff of the food you're offering your worms. If fruit flies become a problem despite good worm feeding practices, you'll need to get control of them sooner rather than later. Fruit flies multiply surprisingly fast in a worm bin and can soon outcompete your worms for food. Start by reducing the moisture level in the bin, keeping the bedding just moist. Hanging fly paper or installing homemade traps can quickly kill adults, breaking the fruit fly life cycle.

Kristi Waterworth

Kristi Waterworth was a regular contributor to Gardening Know How for many years, answering countless queries on plant pests and diseases.