Does Irish Spring Soap Really Repel Mosquitoes and Flies?

I don’t think there’s anyone on Earth who isn’t instinctively annoyed and enraged by flies and mosquitoes.

mosquito sitting on skin

Whether they are just zipping around your head at your cookout or sucking your blood as you’re trying to enjoy some time outdoors, these insect pests are the worst.

Naturally, people go through a lot to try and keep them away. One common assertion on the internet states that all you need to do to get rid of flies and mosquitoes is put out some Irish Spring soap, and that it will repel them.

Is this true? Will Irish Spring really repel mosquitoes and flies?

No, sadly, Irish Spring soap does nothing to repel mosquitoes or flies, though you can use it to make a reasonably effective fly trap.

It’s a big bummer, for sure. I myself like the idea of washing with Irish Spring or carrying a small bag of it around to serve as mosquito repellent rather than using chemical laden bug sprays, but it just doesn’t work out that way.

But, if you want to get to the bottom of this assertion and learn more about keeping flies and mosquitoes off of you, keep reading…


What’s the Story Behind Irish Spring as Insect Repellent?

This is one of those internet rumors, or I guess you could call it an urban legend, that we don’t really know where it came from or where it first popped up. But, like all good urban legends there is a strand of truth in the assertion.

Starting from the beginning, Irish Spring is regularly mentioned as a natural and safe insect repellent, and especially one that works well on flies, mosquitoes and other biting or annoying flying critters.

But where things start to get dodgy is the explanation of why this soap is supposed to work.

The answer entails either some special property of that distinctive Irish Spring fragrance being inherently repellent to insects, or else somehow disorienting, preventing mosquitoes in particular from biting.

The notion is that you either put a bar of soap or soap shavings out where you’re sitting, or else wash with the stuff and you won’t have anything to worry about from either insect.

Another explanation, the one that is sadly just as false, is Irish Spring has itself some of the same ingredients found in commercial bug spray and insect repellent.

The idea, of course, is that you’re getting the same insect-killing power in your soap that you would be in a purpose-made bug defense product. Sadly, we are zero for two on Irish Spring as bug repellent…

Here are the facts: Irish Spring doesn’t do one single thing to either repel mosquitoes and flies, to kill them, to disorient them or to keep them from finding you when you are outside.

It is not some help mask your odor or heat signature or carbon dioxide emissions that mosquitoes use to find you, and flies don’t seem to care about it one way or the other in any capacity.

The “grain of truth” comes in because, surprisingly, Irish Spring does seem to repel wild mammals and even reptiles. Just not insects!

So, sorry: it’s just not true, although I emphatically wish that it was!

How About Irish Spring Body Wash?

A good idea, but no, Irish Spring body wash does not have any insect repelling or killing properties compared to the bar soap.

Does Irish Spring Repel or Kill Insects that Touch it?

No. Based on thorough anecdotal testing, coming into contact with Irish Spring does nothing to harm or kill mosquitoes or flies, or any other insect that I know of.

Or rather, simply sitting out a bar or shavings of the soap is not in any way a protective measure.

But bear with me and I’ll tell you about a way, an effective one, that you can use soap to kill insects dead, including mosquitoes and flies.

Will Irish Spring Actually Attract Flies and Mosquitoes?!

No, thank goodness! You aren’t going to gain any benefits in your fight against mosquitoes and flies from using Irish Spring in any way, but neither is it going to make things harder on you by attracting them.

Strong Soap Can Kill Insects with One Simple Trick, Though

Okay, enough preamble. While it is not true that Irish Spring will repel mosquitoes and flies you can still use soap to kill them and other insects.

But, I will level with you; there are better soaps to use than Irish Spring for the purpose. But if Irish Spring is all you have, or what you want to use, it will still work.

Turns out it’s possible to make an old fashioned but highly effective insecticide by mixing a little bit of vegetable oil, warm water, and soap (preferably dish soap).

Load it into a sprayer, squirt the insects or any other surface you want to protect from them, and that’s all there is to it.

You want to use about two cups of water, no more than a tablespoon of vegetable oil and either a generous shot of dish soap or about an ounce of bar soap, grated. Mix it all together, stir, shake and deploy.

But how does this kill insects? It’s actually pretty simple if you know a little bit about their biology.

Basically, all insects have a hard outer shell or skin, and this hard exterior is covered by a moisture-retaining and protective coating called the cuticle.

Insects must have an intact cuticle or they will die, and as you probably guessed by now, this waxy cuticle covering is severely degraded by the grease-cutting power of soap.

With the cuticle damaged or destroyed, the shell or skin of the insects themselves becomes quite vulnerable to damage and that leads to an increasingly rapid loss of vital fluids for the poor insect so affected. Basically, they will dehydrate and die…

You Can Also Use Irish Spring as Part of an Ingenious Fly Trap

Now, it is also possible to implement so as a passive perimeter defense against flies and mosquitoes, though the method I’m about to share with you works better on flies than mosquitoes because of what they eat; mosquitoes just want blood!

All you will need is:

  • water,
  • a dash of dish soap or some fine shavings of bar soap,
  • a little apple cider vinegar,
  • a small jar,
  • and some foil or plastic wrap.

To make the mosquito trap, take the top off your jar, add apple cider vinegar until the jar is about a third full and then add half as much water to thin down the vinegar. Now add your soap, and stir until everything is blended.

Next, take some thin foil, cling wrap or any other thin but durable covering, then poke some tiny holes in it after you place it over the mouth of the jar and secure it. The holes should be just big enough for a fly to crawl through.

This trap works because it flies are readily drawn to the fragrance of apple cider vinegar, and once they crawl inside looking for a little meal they won’t be able to get back out.

In time, they will tire out and fall, or slip and fall into the surface of the liquid where they’ll be trapped because the soap breaks the surface tension of the water.

Works like a charm, totally safe for people and pets, and easy to replicate in case you need to protect a larger area.

Leave a Comment

Your email address will not be published. Required fields are marked *