What attracts fruit flies, and how do they get into your home?

How do fruit flies get into the house?

As eggs. A female lays her eggs on the skin of ripe or fermenting fruit, and they are often already there when you bring the fruit home. They are about half a millimetre long and barely visible to the naked eye. When the fruit ripens they hatch, and from egg to new fruit fly takes about 8 to 11 days at room temperature. That is why they seem to appear out of nowhere.

What attracts fruit flies when there is no fruit?

Then the source is somewhere else, in a spot that ferments or stays damp. Check the food waste caddy and the compost bin, empty bottles and cans, the kitchen sink drain, wet dishcloths and the mop bucket, damp coffee grounds and old vase water. Start looking where you see the most flies.

Why can fruit flies smell ripe fruit so well?

When fruit ripens or starts to spoil, yeasts turn the sugar into alcohol and then into acetic acid. A fruit fly's sense of smell is tuned to exactly those compounds: where it smells of fermentation, there is food and a place to lay eggs. Bananas, peaches, grapes, tomatoes and apples with a soft spot are favourites. So it is not the fruit itself that attracts them, it is the fermentation.

What attracts fruit flies in the kitchen?

• The fruit bowl, especially fruit with brown patches or damaged skin.
• The food waste caddy and compost bin: waste that has stood for a few days ferments fast.
• Empty bottles and cans: a last drop of wine, beer, juice or fizzy drink is enough.
• The sink drain: they can lay eggs in the damp film of food residue.
• Wet dishcloths, sponges and the mop bucket.
• Coffee grounds, wilted flowers and dough or sourdough left to rise.

How do you get rid of fruit flies in the sink or drain?

By removing the damp film of food residue. Take out the strainer, scrub the plughole clean and flush it with hot water. Do this a few days in a row and put a fruit fly trap next to the sink. A drain can hold fruit flies as well as drain flies; the tape test shows which. How that works is explained in small black flies in the house.

Do coffee grounds attract fruit flies?

Fresh coffee grounds hardly do, but grounds that sit damp for a few days in the filter, a coffee pod or the food caddy do. They start to ferment and go mouldy, and that smell draws fruit flies in. House flies are attracted to fermenting waste like this too. So throw coffee grounds away straight after use or let them dry first. You often hear that the smell of coffee keeps flies away, but there is no good evidence for it.

Are fruit flies attracted to flowers?

Hardly to fresh flowers. To wilted flowers and old vase water, yes: the stems start to rot and the water begins to ferment. Change the vase water every few days, trim the stems and throw out faded flowers in time. If there is a fruit bowl next to the vase, the fruit is often the real source rather than the flowers.

What causes lots of fruit flies in the house?

A source that stays put, and warmth. A female lays hundreds of eggs, up to about 500, and in warm weather they develop faster. That is how a few flies become a swarm within two weeks, and why you see them mostly from June to September. How fast that goes and how to tackle them is in our guide how to get rid of fruit flies.

How do you make your kitchen less attractive to fruit flies?

Keep ripe fruit in the fridge, because fruit flies do not lay eggs there. Close the food caddy properly and empty it more often in warm weather. Rinse bottles before putting them aside, flush the drain regularly with hot water and let sponges and cloths dry.

What do you do once the fruit flies are there?

Remove the source first, otherwise new flies keep hatching. Then put out a trap that mimics the smell of fermentation. The Super Ninja Fruit Fly Trap uses a lure of 37.5% vinegar and 5% apple juice concentrate. In independent testing under the European Biocidal Products Regulation, the trap caught 84.9% of fruit flies within 24 hours, with competing food in the same room (SAGEA, report 4540.SAG, 2021). See the fruit fly traps, or read how to make a homemade fruit fly trap.

Want to know more? Our guide how to get rid of fruit flies explains how fast fruit flies multiply, how long they live and where they lay their eggs.

Authorisation number Super Ninja Fruit Fly Trap: GB-2026-1354-002 (Northern Ireland: NI-2026-1354-002). Use biocides safely. Always read the label and product information before use.