Learn how to DIY a fly trap that actually works using a mason jar (a soda bottle works too) and bait. These results are 100% real from my own backyard using household items and a stinky bait.

This fly trap DIY works so well outside for green bottle flies, aka blowflies, that it'll turn your stomach. How's that for an endorsement? But more than the trap, the most important thing about this DIY - is the fly trap bait.
Living in an almost 200 year old house with backyard chickens means I've learned how to control a lot of pests.
The best time to control pests is BEFORE you see pests. And I know my flies. I dried and counted hundreds of fruit flies while coming up with the best possible fruit fly traps.
Catching flies is a whole lot easier if you start baiting before they start mating.
Get your fly trap made and placed outside a couple of days before warm weather arrives to keep the population under control from day 1.
As with most pest solutions, double whammying is the best way to go. Don't use just one method. Use several. For instance, pair these fly traps with controlling flies with natural predators like parasitic wasps.
When one of my chickens became sick with flystrike, a deadly affliction caused by bottle flies, I knew I had to head into battle against them.
I made and compared a few homemade fly traps including:
- a mason jar with paper cone
- a soda bottle with the top cut off and inverted
- good old fashioned fly strips (not DIY but I had to test them out!)
The results showed the trap wasn't so much the determining factor in how well a homemade trap worked - it was the bait.
Table of Contents
Mason Jar & Paper Cone Trap
Baited with raw shrimp.

SUPPLIES
- Mason jar
- Standard sized sheet of construction paper
- 1 raw shrimp
- water
INSTRUCTIONS
- Roll a piece of paper or cardstock into a cone and tape it together.
- Put the cone into a mason jar of any size, making sure there's room at the bottom of the jar for at least 2" of water. You may need to adjust the shape of your cone.
- Add water and a single raw shrimp to the jar.
- Wait. Within a couple of days your jar will be FULL of flies.
Yep. A raw shrimp allowed to rot in the sun for days until it has the putrid smell of liquid internal organs. That was the key to a successful fly trap.

Soda Pop Bottle Fly Trap
Baited with commercial, store bought fly bait (although not THIS fly bait which actually looks kind of great. I just ordered some.)

This is the basic DIY fly catcher you see all over Pinterest.
SUPPLIES
- Plastic soda bottle
- Scissors
- Commercial fly bait
INSTRUCTIONS
- Cut the top off of the plastic pop or water bottle.
- Flip the top upside down (it'll look like a funnel) and stick it back into the bottle.
- Pour a couple of inches of water into the bottom of the trap and then bait it.
In this experiment I used I used store bought fly bait. The container is a 2 litre pop bottle. The flies can get into the bottle, but can't figure out how to get out. Then they drown.
This trap caught NO flies. Not a single one.
But it isn't the design of the trap that was flawed, it was the bait. Store bought fly bait attracted no flies at all.
Fly bait is the most important part of your fly traps.
Fly Strips
The fly strip cost a couple of dollars and dangled sadly from my window frame enticing no flies at all, just hanging there like a limp tongue.
I wanted to make sure I gave all the fly traps a good shot so I kept them all out for a week. This is how things had progressed after 4 days.
Fly Trap Results



Mason Jar with natural fly bait (shrimp) - Caught HUNDREDS of flies in 4 days
Soda bottle with commercial fly bait - Caught ZERO flies in 4 days
Fly strip - Caught 7 flies in 4 days
After 4 days it was pretty clear that the rotting shrimp was the only way to go in terms of bait.
Would you like to save this stuff?
My homemade fly trap recommendations
The trap
Either the mason jar or soda bottle method will work very well to catch flies outdoors.
The bait
Raw shrimp is your BEST choice for fly trap bait.
For this experiment I only baited the soda bottle with commercial bait (which caught nothing) but since then I've tried it successfully with shrimp as a bait. It works just as well as the mason jar with paper cone.
Testing Different Baits
I experimented with different baits including:
- Fermented chicken feed
- Raw sweet corn
- Fresh chicken poop*
- Raw shrimp*
* If you use meat, seafood or poop understand that this gives the flies a place to lay their eggs. That means if you use any of these things that after several days you will ALSO have maggots appear in your fly trap. Consider this when choosing your bait.
The rotting shrimp was the winner by a shrimpboat load.
The only issue with the enticing smell of rotting shrimp was the vile smell of rotting shrimp. If you place your container up high enough (above nose level) you miss most of the stench but given any kind of downward breeze you suddenly feel like you're walking through a rotting whale carcass.
By day 7 I was pretty sure I would have to try something else because I couldn't stand the stench of the shrimp no matter how well it worked. Then a funny thing happened. By days 8 and 9 the trap was so filled with flies they actually suffocated the smell of the shrimp. Yet somehow the stink was enough to continue to attract the flies.
By day 14 the mason jar trap was almost completely FULL of flies.

Home Fly Trap on Day 14
Because there were so many flies I couldn't smell the shrimp at all and the jar was almost full.
After 20 days it stunk again. Stunk like the guts of a hot monkey. But the stink could have been the mass grave of flies as well.

To save myself some grief and whatever happens to be in my stomach, when it comes time to remove the jar I just tie a plastic bag around my head, put a lid on the jar and throw the whole thing in the garbage.
Just kidding. I don't tie a bag on my head. I'm an excellent breath holder on account of my cat's horrific gut issues when she - coincidentally - eats seafood.
Fly trap placement
The best place to put fly traps is actually AWAY from where your fly problem is. (The dog run/chicken coop/picnic area.) The point is to draw the flies way from wherever it is they're fond of.
Top Tip
To repeat ... the best way to get rid of flies around your house is to use TWO methods.
- Parasitic wasps (really just tiny little flying things that are in no way as menacing as their name alludes to) will kill most flies before they even become flies. The wasps kill them in the larvae stage.
AND
- A DIY fly trap like this (or you can buy a similar sort of trap)
What about indoor flies?
Honestly, I just horsetail them with a kitchen towel.
But you can try this indoor fly bait recipe if you want.
Fly Bait Recipe
- ½ cup water
- ½ cup vinegar
- 2 Tbsps sugar
- 1 tablespoon dish soap (the dish soap breaks the surface tension of the water and vinegar, making the flies unable to use it as a launching pad when they fall in it)
Use either the mason jar or plastic bottle method. You can use a small water bottle instead of a large soda bottle.
Now that you've mostly eliminated one insect from your yard (totally understandable, flies are sex crazed monsters that feed on crap and then land on your corn on the cob), you might want to help out another.
Learn how to raise monarch butterflies on you property, something I've been doing for over a decade.
If you have a great fly bait recipe, leave it in the comments below. If you have a great maggot story maybe just keep that to yourself. Just kidding. Obviously, I'd love to hear the maggot stories.
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Elaine
After the last two days' posts, I, too, am now cured of chicken envy. But I still enjoy reading about sweet Cuddles, etc. I live in Central Texas where we've endured torrential rains and floods this spring and have the mosquito hordes to prove it. The mornings are humid and if I go out to check on my spindly tomato plants without some awful spray on my body, I am immediately attacked. A fan works great (there are quiet ones). I bought Mosquito Beater by Bonide, probably at Home Depot, last year and sprinkle it on my front porch and all around it on the ground, where my plants are. I swear it helps. A sprinkle lasts about three weeks, but I am still using the container from last year. Ingredients are citronella oil, garlic, geranium oil, cedar oil, lemon grass oil, then 87% vermiculite and corn cob. The smell is pleasant - not too strong. There may be other brands, but this is the only one I am aware of. I hate mosquitoes!
Nancee
I loved this post!
I should send you a research paper on the ever-interesting Fruit Fly...then you could test solutions for them!
Linda
I am a wine drinker, (wino). for short. . .and I know for fact that if you walk away from your glass of wine, it will have caught several fruit flies in your absence! So my solution is to put my wine in a mason jar with a lid and drink that one!
Nancee
It's funny~the one trap I use for fruit flies is apple cider vinegar in a jar, covered with some sort of plastic wrap and held on with a rubber band. Then punch several holes into the top and leave near the area of attack. Fruit flies love it and will climb down into the jar for the vinegar, thinking it is rotting fruit. They are now stuck, and eventually drown.
Maybe your wine reminds them of rotting fruit??
Jackie
I just DIY'd the heck out of a brew and not 30 seconds after mixing it, they're were fruit flies ALL OVER the cup!! I was so excited b/c I've tried several that didn't work. All you use is equal parts Apple Cider Vinegar or Balsamic Vinegar and alcohol! I'm sure any kind will do but Vodka was my choice and they swarmed like locust!! If I could I'd leave a pic b/c I was so excited I had to take one to send to my husband! :p Don't judge....we do what we have to do...right?? ;) Hope this helps for all you out there struggling with fruit flies!
Carole
http://www.gocomics.com/calvinandhobbes/2009/05/18
Karen, you kill me! Gawd what a sense of humour!
You had me remembering my favourite Calvin and Hobbes comic strip!
You might be related or better yet, the "girl" version! Yuck! Gross!
This post is the very reason that I keep coming back to your blog!
Love 'ya - silly but brilliant woman!
Deni
Ditto for me! First time reader and I’ll be back for more! Awesome sense of humor and knowledge! Thank you!
ellen
I may try that and hang it from my fence. It's not too far from my trash can and quite near where my neighbor's relatives are living in a tent in his back yard for the summer. Maybe get rid of both annoyances? (he doesn't want them there either)
Kathy
Helping cuddles heal lead to a battle with flies. I really hope it gives you peace of mind about Flystrike. It would make me very anxious about my chickens butts. Careful opening your door as we have laid our vermin problems on your doorstep. It's just you know mosquitoes, fruit flies, and some wasps and I think there are some crawly things that you should look into when you can, hopefully soon. Should it all involve a foul solution, I too would like to place it in my neighbors yard. This is a great group of people. And IRS is funny.
Mary W
I guess around here we call the BAD flies - blow flies. They are the ones that have maggots. So my cottage had fly strips that worked great but they were inside and Not blowflies. We have a large screened porch and don't have blow flies even living in the woods. Did you know that house (not blow/bottle) flies bite just before a rain? TRUE. We do have mosquitos but mostly don't come inside the screen porch enclosure which we were required to put up since we have a pool. The best invention would be to find out what is in certain people that cause them to repel mosquitos when others draw them in like "flies". It is true and even sand gnats (no-see-ums) have body preferences. Why don't scientists figure that one out? Too busy looking for the next best mascara or light bulb filament. Enough rant - thanks for a very enlightening post.
Linda
I just read on another website that mosquitoes are attracted to Type O blood. And dark clothing. I wonder how they figured that out?
Tina
I have type O blood & mosquitos don't like me unless they are desperate & I'm alone, usually early in the morning. My husband is also type O. They love him & it drives him crazy. They don't even look at me when he is around. I guess he's the sweet one.
It would be very interesting to find out why.
Karen Edwards
I have heard that mosquitos are attracted to type O blood, overweight people especially those with diabeties. I'm a O type overweight diabetic and I can promise that they try to suck all my blood out.
Mike
Probably the difference is something like, medications or diets. If I eat a lot of food with garlic they will steer clear of me.
Jennifer
Hi! New here! Stopped by for the fly-ocide tutorial.. but will chime in here.
Hi, I'm Jenn, and I'm a mosquito magnet. I'm type A-, 5'4", 130lbs, not a diabetic (or any other type of itis), and have a body temp of 97.3 that you could calibrate your thermostat to. I don't use flowery or sweet soaps, lotions, or perfumes (more of a 'powder fresh' or 'clean linen' kind of gal), and I'm not overly sweaty. I do however, usually wear dark clothes, and I completely agree - F the new mascara - make the mosquitoes go away before I turn into a giant itchy bite ball of itchiness, sadness, and all of the itching. Because that is a thing, I promise.
aunt bea
Mosquitoes don't bother me since I quit eating sugar. I also have a regular temperature that runs below most people. Neither of those solutions are probably very feasible.
Deborah Mares
People need vitamin B complex to stay health... vitamin B12 has been known to ward off mosquitos. It helps me. (Some say eating lemon grass helps but I have not tried it...since I normally take vitamin B complex daily.)
Also when walking thru the woods, on a dirt path, in Kentucky with my aunt... putting a thin layer of liquid hand soap on my ankles and upwards about 5 inches, I was bite free from chiggers at the end of the walk. I then easily washed off the soap scum. :-)
laura n
So happy Cuddles is doing better.
Ana R.
I am horrified at that last pic of the jar. Holy crow. I've never seen anything more disgusting. But fascinating!
You would think the flies would stay away from a mass grave of their fellows.
Bobbi
Mass grave of their fellows. Laughing out loud.
Raquel
I think I'll skip breakfast now. You creack me up. Your blogs are so honest - I love it! I must admit - I'm impressed and going to give it a go. Do you have any ideas for mice? I have a compost bin in my yard and have found that the mice are getting in there and nothing but leaves, newspaper, fruit and veggies go in there. We also have bird feeders that are also feeding the mice! UGH!
Thanks Karen!
Raquel
Karen
Hi Raquel - The mice are going there for the food, but probably mostly to live. Not sure how to control mice outside. :/ I use old fashioned mouse traps inside. Kills them instantly so it's the most humane. I've tried live traps years ago but if you have 20 or so mice in your house, that's a lot of trapping, driving, releasing, trapping, driving, releasing ... ~ karen!
Inmyelement
Attract birds to your yard. That's how I fixed the problem.
Doriot Kennels
Get a fox terrier or a rat terrier, or even a ratchi. They catch then, kill them and move on. It is a sport to them not a meal, like a cat would do.
Gloria Brown
I saw a post where a home made mousetrap was made and as successful as your fly trap. Use a large bucket half filled with water. Drill a hole on either side at top . Thread a piece of wire long enough to go across from side to side. I missed a step. Put a piece of pipe the size of a cardboard toilet roll threaded onto the wire. The cylinder piece can b made from anything but needs 2 b sturdy and to have a hole thru it to thread the wire. Now coat the roll in Peanut Butter. Insert the roll onto wire and thread wire thru bucket and secure ends so wire doesn't come out. Now and finally put a piece of timber up against bucket to act like a ramp.
The theory is that the mice smell the goodies, run up the ramp , climb onto the roll, it rotates, they fall into the water and drown as they can't climb up plastic walls.. I've seen pictures of like 40 mice in the bucket overnight. Hope it helps.
Hawthorn
A bucket with some water (do not fill to the top), a ramp or some way for mice to get in. Works great. I've found drowned mice in my 25 gallon tubs for the duck's water too. Don't ask me how they got in there but they sure didn't get out again until I dumped their carcasses the next day.
Melanie
Don't know if I could handle a rotting prawn in our hot Aussie summers, but a tried and true alternative is using a teaspoon of Vegemite dissolved in 500ml of warm water in a soft drink bottle with inverted mouth then hung in a tree catches blowflies and fruit flies too and definitely not so stinky as the rotting prawn!!! Might also be a good use of Vegemite for anyone out there who bought it thinking it was some kind of chocolate spread :)
Karen
Well I'll look for some Vegemite. :) I even tried rare cooked steak (leftover from dinner) and it didn't attract any flies at all. But I'll try everything once. :) ~ karen!
Laura Bee
Ha! I bought Marmite once thinking it was Vegemite. Have yet to try either one.
Linda Pottage
Wow, thanks Melanie, definitely trying that one. Good 'ol vegemite.
Linda
Dandenong Ranges
Melissa in NC
Thanks for the lesson on catching flies...I have a very weak stomach and must excuse myself. Good Day.
Karen
LOL!!! ~ karen
Robin
Yeah. I'm down this far in posts and right ...about....ther-
Sue
Mosquitos are weak flyers. Use an outdoor fan, and no problems.
IRS
Sue, you are quite right. I forgot to mention that Consumer Reports said that the only thing that they tested against mosquitoes that was at all effective was a fan. Even then, it only reduced the number of mosquitoes by half, which for me anyway, is not effective enough. Plus I'm not too keen on having a buzzing fan out on the deck on a peaceful night. So hop to it Karen - we need you to figure out a solution for us. Your chickens' butts are safe; now help prevent my butt from getting chewed on.
Debbie
We have two ceiling fans on the outdoor porch and event at high speed I still get bitten to the point of no sleep for the itching. That was pre-Mosquito Magnet.
Peggy
I just recently saw something that said for mosquito bites, take a spoon and run it under hot water until it's hot, then press the bottom of the spoon into the bite. That is supposed to "cook' the mosquito venom and neutralize it. Good luck!
Karen C
If you have basil growing, simply take a leaf, crinkle it to release the oil, and rub that on the bites. This is the only thing that works for me to stop the itch! You could also use basil essential oil. :)
Victoria
You made a version of what we used to get at the tack/feed stores in the '80s. It was called a Big Stinky - and was well named. Big Stinky is a large jar with a lid that works like your funnel. You got to put a liquid (fly death?) and a piece of chicken in it. It got very gross and held about a gazillion flies. The smell could almost knock you down. The fly trap bags are a more modern version and do work very well.
Cathy
Wasp catchers filled with beer will work just the same. They won't catch the volume of your mason jar - so just put a few of them out.
Karen
HI Cathy! This is just a guess, but I think that type of catcher with that bait would probably catch house flies not bottle flies. Again, I'm just guessing tho! ~karen
Kim
I do know that beer bottles with a little left in them are a great attraction for hornets...had that problem in the back yard, couldn't find the nest but a few beer bottles placed strategically around the patio worked great! Dozens per bottle...neighbors will think you are a bunch of drunks but way better than being stung!
Cathy
Nope - we're definitely catching the green iridescent bottle flies. Our dog ended up with a weavel - the size of an eraser. Vet pulled it out and said it was from the larva of these flies.
zoologynerd
This is an old old post, I realise, but your dog must have had a warble, because a weevil is a beetle with a long nose. They (warbles) come from bot flies, not bottle flies.
Maggie L
I had a couple of friends put syrup in a bowl, cover the bowl with plastic wrap then cut slit in it. You should've seen the flies they caught! The bowl was full, THOUSANDS! Gross. But try it, it must smell better than rotting sea creatures...
Ev Wilcox
We don't have much of a problem with flies, but the #$%^&*mosquitos are awful! I too cannot enjoy the deck at night(and lately even the day) and close the doggie door to it as well at dusk. When Dorie Mae comes in the easy riders come in with her, so the deck is off limits to her as well! Hopefully bats are the answer to this onslaught, but that is for next year. Already told my carpenterish husband that I want bat houses for Christmas. Just have to find the plans.
As far as the smell of your very efficient fly catcher-I would move it as far away from the girls, and you, as possible. Who knew rotting shrimp would be the best thing since sliced bread? Well done Karen!
Holiday Bug
@ Ev Wilcox - http://www.batconservation.org/bat-houses/build-your-own-bat-house
Lisa
Mosquitos are out of control. Please find an diy to rid the yard of these blood suckers!
Janet
I'm also waiting with 'bated breath for your KILL ALL THE MOSQUITOES post. Or at least, the one about homemade solutions to keep them off of the people and the poor horse, who has worn a circle in the grass from pacing to get away from the skeeters.
christine hilton
Your next mission is to build a dollarama craft to hide that ugliness.While i have your attention,I made the rhubarb cake last night.I hate Mindy.
Kim
LOL! Poor Mindy!!
Karen
I'll let her know! ~ karen!
Tigermom
You are right. Pinterest lies.
Katie
Hmmm...you could put the lid on and save it for a Halloween decoration!
Mary W
LOL Pin it - you will probably have a gajillion repins!