Flies seem to be everywhere this time of year. Some people prefer to use homemade fly traps. What if you want to simply repel flies instead of trapping them after they’ve already become a nuisance?
I was out at a local farm just yesterday and the flies were very noticeable and quite annoying as I went about my work. Seeing all those flies reminded me of a simple, non-toxic, and very effective fly repellent that I observed in action at one of my children’s field trips a couple of months ago.
The class was visiting a petting farm with a large open barn where donkeys, horses, goats, and other livestock were available for the children to observe and interact with.
Despite so many animals in a small semi-enclosed area, there were no flies buzzing around! Curious, I asked the owner about this, and he pointed to the heavy-duty plastic bags partially filled with water hanging over every stall.
He explained that a clear bag of water with a penny at the bottom would repel the flies very effectively. He went on to explain that the “eye” of a fly is actually hundreds of eyes and the reflection of light on the bag of water keeps them away.
“Why the penny at the bottom of the bag?”, I asked.
Grandpa the farmer answered that he wasn’t exactly sure but the penny did seem to increase the effectiveness of the hanging bag of water alone. He added that he didn’t know how many square feet each bag covered so he just put a bag over every animal stall to keep as many flies away as possible.
He also had put up a few bags over the picnic area and it was so nice to be able to eat lunch without flies swarming everywhere!
Note that the clearer the water, the more effective this trick is. If you use rusty well water, it won’t work as effectively as ultra clean and clear filtered water.
Try this fly repellant method for yourself! If you do, please check back and let us know how it worked for you!
Fly Repellent Only Works for Flies
Please note that this fly repellent trick only works for flies, not mosquitoes, and other insects. It also works very well for flies in the Southern United States. However, it may not work as well for flies from other geographical areas such as blowflies in Australia.
If you need to repel other insects like mosquitoes, ticks, or horse flies, this article on natural herbal insect repellent can help.
More Natural Pest Control  Ideas
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Nontoxic Pest Control Ideas that Work
Natural Fire Ant Killer that Works FAST
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Natural Flea Infestation and Prevention Strategies
Attracting and Using Ladybugs for Garden Pest Control
Safely Get Rid of Carpenter Ants in a Snap
Spider Repellent Guaranteed to Work
Mosquito Bite Remedy
I used a freezer Zip Lock bag and filled it half way with water then squeezed
out most of the air and sealed it. I then made a small hole in the double thickness
just below the zip lock and place a small “S” hook and hung it in my garage from a
hole in my garage door opener. I now have two out there, I added one over where
my trash container sits. They seem to work great……..
If your theory that the bag confuses the flies’ eyes is true, than something equally as optically confusing should work as well. Has anyone tried just hanging up a fresnel lens? They’re obviously more expensive than a bag filled with water, but it might explain how this phenomenon works.
What is a fresnel lens?
This is amazing….went on a trip to Gulf Shores where I was introduced to this! Actually is very effective! Weird, but effective!
This was busted on Mythbusters.
Any ideas for bees/wasps/hornets? I see someone said the bags also work for them, and I’ll try, but with such mixed reviews. And we’re in a rental, so can’t try painting the deck top blue. We have nests everywhere on our building, and they’re only growing…already called prop mgmnt, who’s called the association, however, in the meantime, I have two kids (who with family history may or may not be allergic to stings!) away from them! HELP please!!! Thank you!
When it starts to turn dusk, keep an eye on where the hornets and wasps are going. That’s where they spend the night. There a hornet/wasp killer spray that has a long thin straw that you attach to the nozzle. Shake the can well first before attaching straw. Insert the straw with can into the hole/entrance to the nest and spray well. A foam comes out filling the inside space and blocks the hole to get back outside. Next morning, smothered, all dead.
Leave the bees alone though! We need them and they are not aggressive at all. If a bee is on the grass and accidentally stepped on, it would only sting in self-defense. Also, bees don’t have the same kind of nests that hornets and wasps do. Often in the evening I will see them wrapped in the petal of a flower after a long days’ work, so sweet to see.
I think hornets and wasps belong to ISIS! They are just plain evil.
I am going to try this. Every time we cook out, when we gather around the picnic table we are swarmed by flies. Hope it work. Can’t wait.
I think Arkansas flies are too stupid to know this is supposed to ward them off… Had 2 bags for a small area – didn’t work…
For fruit flies: in a jar pour 2 tbs apple cider vinegar or red wine vinegar and a drop of dish soap, I use Dawn (apple). Set on a flat surface. They dive right in and die.
For mosquitos: pour listerene (original) in a spray bottle then cover the grounds outside. O haven’t done this yet, but I hear it works!
I tried the ACV in a jar with a drop or two of Dawn. It took a few days to catch a couple flies. Then I tried again, adding some sugar. Wow! In one day, I caught 10 fruit flies! Thank you for the suggestion.