Full Guide How To Get Rid Of Cluster Flies Naturally

Cluster flies aka attic flies get their name from clustering together in large numbers over the winter months. Cluster flies habits mean that they are no real risk to human health like most common flies but they are a nuisance. They are known to give off a sickly odour and they also have a big effect on earthworms around your home.

The reason they aren’t a risk to human health is because they are not interested in your food although they do like to live in your house.

What do Cluster flies look like:

They are 6mm-8mm in length and are normally they have dark colours such as olive, black and grey. Some species have black and silver patterns on their abdomens. Cluster flies look a lot like House flies although they are visibly slower moving and unlike the House flies their wings overlap. They a re also normally larger than the common House fly and mature adults have golden hairs on their thorax.

get rid of cluster flies

What they do and what attracts Cluster flies:

Cluster flies like to lay their eggs on lawns, areas that have earthworms within the soil. This is because the larvae of a Cluster fly are an earthworm parasite that requires earthworms to grow into full adult Cluster flies. When September arrives the cluster flies with start to look for a place to hibernate.

They will look for any small cracks or crevices that will gain them entry to structures. Roof spaces, Wall cavities and attics are common places for cluster flies to stay over the winter. The problem with this is when they emerge in the summer months. They can literally full your windows with flies as they try to leave. When disturbed the cluster flies give off a sickly odour which is not want you want in your home.

Cluster flies are a nuisance in your home because they leave strains on walls and curtains. If they die they also attract other unwanted pests into your home such as larder beetles.

How do you know you have a Cluster fly infestation:

One sign you may notice of a cluster fly infestation is more and more of them on the warmer days, these flies are more active on sunny days and you will be able to notice more fly activity. Mainly around your windows you will find more flies than normal this may be a sign that you have a cluster fly infestation somewhere in your home.

If you find dead flies on your window sills have a closer look you may find it to be a cluster fly. If it is then there is a very good chance that you have cluster flies somewhere in your home.

How to get rid of Cluster flies:

The most common method to get rid of cluster flies is by using pesticides although I like to avoid this and get rid of cluster flies naturally. So here are some tips to get rid of cluster flies naturally:

Before infestation:

1 – The best way to stop problems in your home with cluster flies is to simply deny them access. First you need to go around your home and check for all potential areas where they can gain entry. Look for all small cracks and crevices in your brickwork, doors, windows and roof fascia’s.

2 – Once you have identified potential problems areas you will need to take the time to seal and close up all these gaps. I recommend you use some high quality silicone which you can buy cheaply from your local DIY store.

3 – I don’t recommend you use pesticides to kill the flies in your home unless you can clean up the dead flies afterwards. This because using a powder pesticide may kill hundreds of flies inside your wall voids. This will attract other unwanted pests.

After Infestation:

1 – If you have an infestation inside your home already, then you will need to take more direct measures. Placing homemade fly traps near your windows is the best way to catch and kill cluster flies.

2 – You can make an effective Cluster fly trap. By picking up some Mouse glue traps cheaply online and then you’ll need some plastic food trays. You may have to cut the mouse glue trap with scissors so it fits in your tray.

Secure the mouse glue trap inside the tray using some duct tape or double sided tape. Then remove the mouse glue traps protective paper on the glue. All you need to do then is lean the trap at an angle on your window. The bottom of the trap needs to be on the window sill and the top leaning on the window itself. Make sure the sticky side is facing the window, the gap you leave for the flies to enter need not be very big and you may wish to secure the top of the trap to the window with another strip of tape.

3 – You can also use these bug zappers in your attic. At the beginning of spring it can sometimes be worth putting a bug zapper in your attic the cluster flies will be attracted to the light and then will be zapped by the LED lantern bug zapper, you can go and clean up the dead flies with ease.  This will also stop the flies from being able to escape and inhabit other parts of your home

4 – Another option is to use natural herbs and plants to get rid of cluster flies. I recommend Citronella plants that you should plant around the entrances to your home. This will repel the cluster flies and stop them from entering to hibernate.

To prevent further Cluster fly infestations:

To prevent further cluster fly infestations make sure you seal up all entry points before the end of summer. You will want to cover vents with fly meshes, fill all cracks and crevices with silicone. You can also use natural herbs to prevent the cluster flies wanting to enter your home. Having herbs like mint, basil and lavender will give off odours that will repel cluster flies.

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  1. I’m glad my coworker recommended this website to me. My family loves to barbeque and your tips and advice has really helped us enjoy these gettogethers without flies getting in the way.

  2. Herbs from the mint family are a great tool to use to get rid of these pests. I dissolve menthol crystals with warm water in a spray bottle, spray my window sill and screen, and all those bugs (gnats, mites, and flies) scamper away, hahaha.

  3. Is it safe to leave a bug zapper unattended, though?

  4. July 20, 2017

    Where do you find Menthol Crystals from ?

    Thank you.

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