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The Poop Scoop, How To Get Rid of Fruit Flies
November 25, 2012

Get Rid of Fruit Flies...For Good!

Please...Just Go Home!
Have you ever had any guests show up uninvited and would never leave no matter how many hints you gave them? That's right! You know who (or what) I'm talking about. That's when you have to entice them to drink more. I'm mean you literally have to drown them in their favorite drink. Apple Cider vinegar!

In this issue of the Poop Scoop. I'm showing you how to get rid of fruit flies. No matter how or where they got in they just have to be dealt with and if they can't take a hint then you just have to kill them. Sorry to put it so bluntly but they will invite their friends and then their friends will make more friends and so on and so on.

I was addressing an email the other day with one of my readers and they brought up a great question that I thought I would talk about in this issue of the Poop Scoop. It's that time of year when many of you have brought in your worm bins from outside to keep them from freezing and to keep them highly productive throughout the winter. Good call if you did.

But you may have also brought something else in that rudely RSVP'd themselves like the loud, smoking and drinking, obnoxious kid we all grew up with in high school. No matter. Because the best way to fight fire is with fire.

How to Get Rid of Fruit Flies
You have an abundance of fruit flies so let's first discuss why.

  1. Fruit flies are attracted to excessive moisture.
  2. They are also attracted to fruit.
  3. And they are attracted to acidic liquids such as the sour smell in the worm bin.

You can deal with this problem but let me tell you that this is never going to be a quick fix. The adult flies, as long as they are alive and have a food source will keep multiplying and the cycle will not end until every last fly is gone (or at least deterred from mating).

So this is what I would recommend

  1. Drown them. Use a small container, fill it with apple cider vinegar, cover the top with plastic wrap, and poke enough holes in it and big enough for the flies to get in and drown. The more containers the better. Go wild!! I use this myself. I have not found a better liquid yet. They love the sour acid.
  2. Some worm flow-through systems come with a spigot at the bottom of the system. This is for collecting the leachate at the bottom of the last tray or bottom reservoir. If you're always having liquid at the bottom then this can be a problem. It will definitely attract the fruit flies but usually only if it has a sour smell to it.

    If it does then you are putting too much food in and the worms cannot keep up with the amount. Remove any excess food you have in the bin and you really should never have any run-off as there is always enough moisture within the food itself to keep your worms hydrated.

    Spigots aren't always a bad thing as sometimes it can be easy to over do it especially for beginners. Be sure you do not use the smelly leachate and know the difference between leachate and worm tea.
  3. If you need to add food then go ahead and add some food to the bin in a couple of corners and cover it with moist coco coir or peat moss of about 3 inches. This will prevent any adults from getting in and laying eggs. They now should be drawn to the the apple cider vinegar.

    Installing a layer of peat moss or coco coir on top is important because it is dense unlike shreds of paper or cardboard. It will also prevent the buried food from leaking any smells out into the room.
  4. Add Diatomaceous Earth (DE) to the very top of the bedding. Just sprinkle it in all over the top bedding. This will get on the flies and rip them to pieces and dehydrate them. At least any that hatch or get back into the bin. Not a must if you have no access to DE. This is perfectly safe for humans and worms.
  5. If you have an insane amount of fruit flies then use the vacuum and suck them up when you can catch them off guard. You have to be quick!

You will eventually get to the end of the cycle (pupating and hatching) and things will be back to normal. This is what I have found that works the best and if you have any suggestions then I would be glad to hear them from you. Just go to and post your comment.

We always enjoy hearing and being helped from the community.

Happy Worm Farming,
~Pauly Piccirillo

Teaching, Inspiring and Empowering you to become the best worm farmer you can be.

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