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Thursday, 24 June 2021
Blow Fly Control | How to get rid of blow flies in my house

Blow Fly Control | How to get rid of blow flies in my house

Morphology of the blow fly 

The blow fly is a fairly common pest that resembles house flies in both look and behavior. There are a few different variations within the blowfly family, most notable of which are the screwworm, the green bottle fly and the cluster fly

There are over 1200 types of blow flies in the world which are found in almost any well-populated area. No matter the variation of the blow fly, they all look similar, making them fairly easy to identify. Although similar to house flies, they are slightly bigger and have big heads with tough bodies. Blow flies are metallic in color and are usually green or blue in this metallic hue.

Blow flies are attracted to any animal carcass so they are often found around dead animals. Adult blow flies can lay eggs in either manure or the carcasses of animals. They can therefore be found laying eggs in large numbers which then develop into fly maggots who feed on dead animals until they reach maturity and become fully active blow flies. 

If the above description sounds familiar to you, and you believe you might have a blow fly infestation, contact Vextermination!

How long do blow flies live for?

The life cycle of a blow fly is known as metamorphosis because it goes through the stages of egg, larvae, pupa and adult. Once the adult fly has laid her eggs, it takes her as little as 24 hours to develop into larvae. 

The larvae, which resemble maggots, then feed on the animal carcass in which it has been laid in, which causes the carcass to bloat (hence the name blow fly). It then goes through a couple of weeks in the pupa phase until it becomes a fully grown adult. This entire process takes around two to three weeks to complete. Once the eggs have fully matured into flies, they then can live anywhere from two weeks to a month. 

Why do I have blow flies in my house?

There are a few reasons as to why you could have blow flies in your house. They could have flown in from open doors, windows or cracks in your walls. If you have an animal, they could be attracting the blow fly for a number of reasons.  

Blow flies might initially be attracted to the feces left by your pet outside and migrate inside if they smell something appealing to them. Alternatively, if your pet has an open wound, female blow flies might see this as an opportunity to lay their eggs for breeding. 

Other than that, blow flies are most attracted to rotting things. This could be rotting meat, rotting vegetables, rotting carcasses, etc. Therefore, if you see active flies in one specific area, analyze the area to find out what could be attracting them. This could be something like a compost pile, a small animal carcass, etc.

One of the most difficult aspects of blow fly control is that once the adult blow flies have entered your house, there is a chance that they will lay eggs inside, which can cause you more problems down the line.

What is the difference between a house fly and a blowfly?

Although a house fly and a blow fly share some visible similarities, there are also some key differences between the two which help differentiate them. The main visual difference between a house fly and a blow fly is their coloring. House flies tend to be much darker and do not have the metallic hue that blow flies possess. Instead, house flies have small hairs that cover the main area of their bodies. 

Moreover, house flies are attracted to all types of food and carry a plethora of pathogens on them that can spread and cause disease. Blow flies, on the other hand, are usually attracted to things that you would not eat, even if it is food. For example, they are routinely attracted to rotting meat and compost. You will also see blow flies surrounding garbage and feces which house flies do not tend to do.

Signs of a blow fly infestation 

Although they are active year round, blow flies are most commonly seen around summer time as this is when the flies are active the most. Therefore, summer is the time when you should be extra alert to the possibility of a blow fly infestation. 

It is fairly easy to spot a blow fly infestation as they will be a nuisance in your home or in your garden and on your lawn. Blow flies generally gather around a specific area so the high concentration of them in one place makes them fairly easy to spot. 

Moreover, a fairly self-explanatory sign of any kind of fly infestation is the constant buzzing sound that you will hear. Even if you cannot see all the flies that are in your house or garden, you will undoubtedly hear that infuriating buzzing sound.

Spotting the signs of the larvae is far more difficult as they are usually hidden within wounds, carcasses or feces. However, when they begin the pupating process, they will emerge from these breeding sources and might be easier to spot. The best thing to do if you suspect you have a blow fly infestation is to contact a pest control expert

Expert tips to get rid of blow flies in your home 

Remove breeding grounds

Identifying where the flies are coming from and where they are breeding from is essential to get rid of blow flies and the first thing that must be done in your pest control journey. Usually, the source of breeding for blow flies will be garbage, dead animals or feces. Therefore, if there are any of these in or around your house, you should clear it out.

Removing dead rodents in your garden, animal feces, garbage or a compost pile will remove the source of the problem. Once you have thoroughly cleaned these areas, there will no longer be anything to attract the blow flies and they will likely move on to a new breeding ground.


If there are still blow flies around or inside your house after you’ve removed the breeding grounds, you can invest in an insecticide to get rid of the remaining flies. Most insecticides are designed for outside use only, so make sure you read all the instructions of the product you buy before you use it. Once you are confident you know how to use the insecticide, spray it on the affected area and let it do its work. 


If your blow fly infestation is inside your house, you can use an aerosol. There are aerosols available that are predominantly used to kill insects in your house. These aerosols work by attacking the insects when they come into contact with the spray, hence quickly killing them. Although these are safer to use inside your house than insecticides, you should still ensure your home is properly ventilated and you keep windows open for at least 15 minutes after administering the spray. 

Fly traps 

Another method for eradicating blow flies inside your home is fly traps. There are two kinds of fly traps which are electric fly traps and glue fly traps. Glue fly traps are better for indoor use whilst electric fly traps are usually used outdoors. 

Glue fly traps are sticky bits of paper that you can put on your walls, windows, floors or really any surface. When flies land on these pieces of paper, they instantly get stuck. From here, once a few have been collected on the paper, you can peel the paper off your sources and throw it away, along with the flies. 

Electric fly traps are the ones that hang outdoors. They are usually attached to a porch, gutter, or garage. These attract flies through the light that they give off. Once a fly is attracted by the light, they fly into the trap and are electrocuted. 

Pest control

Although there are different things you can do to get rid of a blowfly infestation on your own, nothing compares to hiring a professional pest control company

Hiring a pest control company such as Vextermination will ensure a thorough job is carried out and all the blow flies in your house are exterminated. We offer different packages to offer our clients quick, efficient, eco-friendly and safe extermination services