Key takeaways
- Flying ant day is the mating flight of black garden ants, the common ant in UK gardens
- It happens on warm, humid, still afternoons, mostly in July
- There is no single date; flights roll around the country over several weeks
- The winged ants are new queens and males; they don't sting and are gone in hours
- Gulls, swifts, starlings and blackbirds feast on them
- Sweep them up and shut the doors; boiling water and ant powder aren't needed
Flying ant day is the mating flight of the black garden ant. On a muggy summer afternoon, thousands of nests release winged ants at once, and for a few hours the air fills with them. It’s completely normal, it’s harmless, and it’s over by evening.
Here’s what’s going on, when to expect it and the easy way to deal with ants on your patio or near the back door. If you’re after help with ant nests the rest of the year, the guide to getting rid of ants in the garden covers that.
What is flying ant day?
Flying ant day is the nuptial flight (mating flight) of Lasius niger, the black garden ant. It’s the ant in almost every UK lawn, border and patio crack.
For most of the year you only see the wingless workers. Once a year, each colony raises winged new queens and males. On the right afternoon, they all leave the nest and mate on the wing.
- New queens are the big ones, around 1cm long
- Males are much smaller and slimmer
- Workers stay on the ground and don’t fly
The males die soon after mating. Each mated queen lands, snaps off her own wings and looks for a crack or patch of soil to start a new nest. A queen that succeeds can rule her colony for many years.
A new queen is the biggest ant you’ll see on the day. Once she’s mated, she’ll pull off her wings and dig in.
Why do all the ants fly at once?
The weather sets them off, not the calendar. Nests across a whole town wait for the same conditions, so they all go within the same few hours.
The ants want:
- Warm air, typically on a hot afternoon
- Humid, muggy conditions, often after rain
- Still air, with little or no wind
Flying all together is a clever trick. There are far more ants than the birds can eat, so plenty survive. It also mixes queens and males from different nests.
That’s why the date moves about each year. A hot, settled July brings flights early. A cool, wet one pushes them later.
When is flying ant day in the UK?
There’s no single national flying ant day. The name sticks because one big flight often happens across a region at once, but flights roll around the country over several weeks.
- Most flights happen in July
- A very hot June can bring the first ones early
- A cool summer can push some into August
- One muggy afternoon can set off a whole area at once
You’ll often get a day’s warning. Watch for workers bustling about at nest holes and winged ants gathering just inside the entrances. A hot, close afternoon after a cooler spell is the classic signal. Handy if you’ve got washing out or a barbecue planned.
Why flying ants are good news for wildlife
Flying ant day is a feast. Gulls, swifts, swallows, house martins and starlings snatch the ants from the air. Blackbirds and robins hoover up the ones that land.
Gulls can’t resist a flying ant swarm. You’ll often see them wheeling low over towns and seafronts on the day.
The rest of the year, black garden ants do useful jobs too:
- Their tunnels help air and water into the soil
- They carry bits of plant and insect matter underground
- Green woodpeckers and other birds feed on the nests
They’re not perfect garden friends. Ants “farm” aphids for their sweet honeydew and will guard them from ladybirds. If that’s happening on your plants, the guide to getting rid of aphids has gentle fixes.
Ground-feeding birds such as blackbirds clear up the spent ants, so the lawn is usually tidy again by the next day.
What to do on flying ant day
Very little. The flight lasts a few hours and nature tidies up after it. If the ants are in your way, these jobs help.
On the patio or path:
- Sweep them up with a stiff broom and dustpan
- Tip them onto a border or lawn for the birds
- Hose the paving with plain water if you want it clear sooner
- Give it an hour or two; most will simply fly away
Keeping them out of the house:
- Shut doors and windows on the sunny side during the flight
- Wipe up crumbs and sugary spills near the door
- Vacuum up any strays indoors and empty the bin outside
On the morning of a flight, ants gather along patio joints before they go. A broom clears the surface without harming the nest.
Do you need boiling water or ant powder?
No. Pouring boiling water into the cracks scalds nearby plants and lawn. It rarely reaches the queen, and the nest soon recovers.
Ant powders and sprays aren’t needed for a flight that clears itself in hours. They also kill other ground insects and the ants the birds would have eaten. If a nest causes real trouble later in the year, use an approved product made for that job and follow the label.
When are ants actually a problem?
Flying ant day itself is never the problem. Ants are only worth acting on in a few cases:
- A trail into the kitchen, week after week
- A nest that keeps lifting and tilting patio slabs
- Big ant hills that make a lawn bumpy to mow
For a trail indoors, find and seal the gap, and keep food in sealed tubs. For nests under paving, the guide to stopping patio ants covers relaying and refilling joints. In a lawn, brush ant hills flat on a dry day before mowing. Thick, healthy grass copes much better, so feeding your lawn at the right time helps.
A yard brush and a couple of minutes is all it takes. No boiling water, no powder, and no harm to the nest below.
Common mistakes on flying ant day
- Reaching for chemicals. The swarm is gone by evening. Spraying just harms other wildlife.
- Pouring boiling water on the cracks. It kills plants either side and the nest bounces back.
- Leaving doors open. A few minutes with the back door shut saves a lot of sweeping indoors.
- Panicking about stings. Black garden ants have no sting, so there’s nothing to fear.
What black garden ants do through the year
| Month | What the ants are doing |
|---|---|
| January to February | Nest quiet deep underground |
| March to April | Workers start foraging as the soil warms |
| May to June | Winged queens and males raised inside the nest |
| July | Main flying ant day window |
| August | Late flights after a cool July |
| September to October | Workers busy, then slowing down |
| November to December | Colony resting for winter |
Frequently asked questions
What is flying ant day?
It’s the mass mating flight of black garden ants. Winged queens and males leave their nests together and mate in the air. It happens on warm, humid, still afternoons, usually in July. The ants are harmless and gone within a few hours.
When is flying ant day in the UK?
Usually in July, but there’s no single fixed date. Flights depend on the weather, so they roll across the country over several weeks. A hot, muggy, still afternoon after a cooler or wetter spell is the classic trigger. A cool summer can push flights into August.
Are flying ants dangerous?
No, flying ants are harmless. Black garden ants have no sting, and the winged ants are busy mating, not looking for trouble. At most one might give a tiny nip if trapped against skin. They don’t damage plants or houses.
How do I get rid of flying ants on my patio?
Sweep them up with a stiff broom and wait. Tip them onto a border or lawn where birds will clear them. Hose the paving with plain water if you want it clear faster. Within a few hours most will have flown off.
Do flying ants mean I have an ant problem?
No, it just means there are healthy ant nests nearby. Almost every UK garden has black garden ants. They only become a problem if they trail indoors to food or a nest keeps lifting paving.
Are flying ants harmful to dogs and cats?
No, black garden ants aren’t poisonous to pets. A dog or cat that snaps at a few will come to no harm. Just make sure pets have plenty of water on a hot, humid day.
Now you know what flying ant day is all about, see how to create a wildlife garden that keeps the birds coming back all year, or browse more garden wildlife guides.
Our team produces practical UK gardening guidance from source research, contributor records and established horticultural practice. Editorial standards are overseen by Matt W.
