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.
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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I have always fruit flies at home. I made these traps but they didn't work.
Can you please show me some other ways.
Thanks
Hi Yalda. This isn't actually a fruit fly trap, it's a trap for regular house and bottle flies. This post https://www.theartofdoingstuff.com/best-fruit-fly-trap-world/ features a similar trap but specifically for fruit flies. ~ karen
Helpful
Also I found a good fly trap
http://amzla.com/tocveou72h4j
Do you like it?
I read one from a southern gal who used syrup (about 1/3 of the jar full) and one hot dog wiener cut up and dropped into the syrup - she also didn't have a cone, just used the top of the jar lid and punched about 3 holes in it to let the flies in. She professed the stink was kept to a minimum thanks to the syrup and it caught a whole PASSEL of flies (southern for "gobs".) :-)
Karen,
First off I would like to say good ingenuity with this project. The thoroughness on your step by step process was greatly detailed and much appreciated!
That being said would you possibly do this project again to better research which method truly works the best?
There are missing factors going into place with your research that are skewing your results as follows.
- Subjects are too close together to see a true attraction.
Each subject is on one wall in the same time frame. We could see dramatically different results if you observe each one in different time frames. Also, I would like to see if the rotting shrimp actually end up attracting more flies thus resulting in a bigger problem.
- Could you add another product and different makes?
I've tried two different fly strips in the past and one actually did work better. Another product I would suggest is one of the catching bags you can buy at a farming supply store because they claim to have a special attractant made just for flies. Which might be true I have one for wasps that I tried for a week but I wanted to see if it would catch hornets and/or bees as well. It only caught yellow jackets specifically. I was surprised, happy it didn't get my honey bees and only caught the wasps. But disappointed it didn't get my bald faced hornets.
Any ways that would be great if you could! Either way I will be watching your blog for further posts and results. This is my first time visiting but not my last!
Personally I've been using these for years anything stinky will attract em I've used blood from a steak package or chicken skin and half full of water I don't leave it in the sun for days just all to water place screen cone n I've cough them from the very first hour.
All I can say is you are hilarious!!! I'm new to being a Chicken mom and have learned so much basic and common sense from your posts. The real value is the laughter that erupts periodically that sometimes scares my husband!
PS. I'm very sorry about Cuddles.
What kind of paper did you use? does it matter?
CEDARCIDE-biting insect spray-people, pets and premise. cedarcide.com.
This is the greatest product we have EVER used...no ticks, mosquitoes,etc. etc. etc.
You will NOT go wrong in using this product...we even put cedar shavings and cedar sawdust around our cedar shake house....does not keep the ding-a-ling moles out of the cellar but..
Growing up on a horse farm, we used a similar flytrap... milk jug with a small hole cut where bottom of handle meets jug. Rancid meat and couple inches of water poured through cap... replace cap and hang in out of the way area. It can be left there for a month or so before putting in trash and getting another milk jug. They do have a product on the market that comes with a plastic jug and you can refill them, but it smells like rotting meat and who wants to refill that jug?
I tell ya, there's nothing grosser smelling than rancid shrimp, lol. Ouff. Rancid meat would be a step up, lol. ~ karen!
what is the liquid in the jar? And do the flies just die from hitting the liquid?
Got a facebook post about flystrike which led me to your post about cuddles, and then on to your fly trap. I'm making the glass jar trap tonight as a preventative. The flies are out of control this year and I want nothing to do with maggoty vents. (I'm a newbie chicken momma) That is the scariest s*&% I'd read about chicken raising to-date so thank you for being so blunt and colorful with your language. I need a good dose of reality and a good laugh.
Hi, I know I'm about a year late, but I found this post while trying desperately to find a solution to our fly problem.
However, I live in a duplex with a car wash on one side and a funeral home on the other (guess which side the bottle flies come from?), with a tiny yard because the back is a parking lot. I'm pretty sure the funeral director/our landlord wouldn't appreciate the smell of something rotting when people show up for funerals. Have you heard of any less smelly options? I know the flies are coming from outside, since I see them hanging around the windows before they find a way in. I can't really stay downstairs because they just really seem to love me for some reason! (I shower, I promise!) It'd be nice to enjoy my own house during the summer....
As a matter of fact I just did a post on that very topic last week Erica. :) https://www.theartofdoingstuff.com/parasitic-wasps/ ~ karen!
how about putting thin netting over your patio, you might have to build the frame for it, but that is what they do in africa and places that have mosquitos...just a thought:):
If anyone is new to Karen and her DIY life/blogs, the following is a link to what I was talking about the raising of Monarchs, appropriately named as the King of Butterflies.
https://www.theartofdoingstuff.com/video-of-monarch-caterpillar-emerging-from-egg-a-monarch-project-update/
"walking through a rotting whale carcass" " Stunk like the guts of a hot monkey"
Karen,
In what part of your current life (or previous life) did you come to experience these wonderful olfactory events to be able to compare for this blog?
I personally have had so many nasal polyp surgeries that I have no sense of smell. So guess who got to change our kids poopie diapers?
Plus I have 5 Monarch caterpillars in a jar in my kitchen that your blog inspired me to raise to help them make it to Mexico this fall.
Thanks,
Dale
Oh Dale ... My nose and I get around. Good job on the monarchs!! ~ karen!
Ok, so here's my question...what about rain?? Does it fill up the jar? I live in Tulsa, OK and the flies (and Mosquitos for that matter) are insaaaane!! We were going to put a trap out like yours, but wondered if the rain would affect it?
Sincerely,
Flies and Loathing in Tulsa
Hi Micah! My jar is placed under my eavestrough so even with a downpour it doesn't get rained on. I have seem some people make a little lid for it out of a plastic lid from a yogourt container (or something like that). Just punch a hole in the lid and run the string hanging the jar through it. Tie a knot in the string about an inch above the jar to allow the flies to still get in. ~ karen!
I'm seriously hitting the jackpot as far as posts go today! This is totally disgusting! I, of course, had to be eating lunch while reading this too. That was stellar planning on my part. I should now by now how unpredictable your blog is. BUT, major kudos on doing whatever you had to to help Cuddles! I'm glad she is feeling better!
You are one brave woman Karen! But one that loves her chicks!!
That's a shit load of flies in the last pic! Holy gross..but oh so fascinating. lol!
i have made several diy fly traps. The bait that works best for me I found by accident. I have started making water keifer. This ferments for 24 hours. Then I strain it and pour the water into a jar with 1/4 cup of fruit juice and cap it. This second ferment is ready in 12-24 hours. My kids love this healthy "soda". But I found that flies do too if it's left out. So I put it in the fly trap. The longer it sits in the trap, the more it ferments and the more flies I trap. I no longer have fruit flies in the house and I keep a trap on the porch to slow the influx of flies into the house.