It seems like everyone knows at least one homemade horse fly spray recipe that uses natural ingredients (by “natural” we mean a recipe that doesn’t contain man-made insecticides). Our friends at we decided to take three homemade horse fly spray recipes, and one semi-homemade recipe, and put them to the test. We wanted to know if the homemade fly sprays with natural ingredients would actually keep flies from biting our horse, and if so, for how long. We chose the recipes we tested based on simplicity, ease of finding the ingredients, and a lack of ingredients (like Pine-Sol) that might be irritating to the horse.

CAUTION – Use any fly spray recipe on this page at your own risk.
We are in no way suggesting any of the recipes below are safe for you or your horse.

The Homemade Horse Fly Sprays – How We Tested Them
Before we get to the fly spray recipes, we should probably tell you a little bit about how we tested them. Although our testing procedure was by no means scientific, we did try to be consistent with the testing conditions while we tried the different fly sprays. Here is what we did when we tested each of the recipes found a little lower on this page:

  • We used the same horse for all of the tests.
  • We caught the horse and did our tests at about the same time each day, and during approximately the same weather conditions.
  • After we caught the horse we sprayed him with fly spray, groomed him, and went for a ride in the same locations around the house, barn, and pasture.
  • The season we tested in was late spring / early summer. The temperatures we tested in varied from the mid-to-high 80 degrees Fahrenheit to the low 90s.

Homemade Horse Fly Spray Recipe #1


  • 2 cups white vinegar
  • 1 Tablespoon Eucalyptus oil
  • 1 cup water

NOTE: To learn more about Eucalyptus oil please scroll to the bottom of this page.

Mix the ingredients together in a spray bottle. Shake well before every use and spray the horse.

Natural homemade horse fly spray ingredients

The Results
For house flies and stable flies, this recipe worked very well. In our opinion, it worked better than several store-bought fly sprays we had recently used. It wasn’t perfect – the house and stable flies still landed on the horse but the actual bites he experienced were definitely less.

However, it was a different story with deer flies. When we rode the horse away from the barn and house and out into the pasture the deer flies swarmed to him like he was a free, all-you-can-eat buffet. The fly spray seemed to be of little or no help as the deer flies bit him constantly, all over, and in large numbers.

How Long It Lasted
This fly spray lasted between 45 minutes and an hour. It did work well for house and stable flies during that time.

Our Opinion
For house and stable flies we liked this fly spray recipe. It only has three easy-to-mix ingredients, and the ingredients are all natural (remember, as we stated above we’re defining “natural” as an ingredient that is not a man-made insecticide). However, it did not work at all for deer flies.


Homemade Horse Fly Spray Recipe #2


  • 1/2 cup hair conditioner for humans (the kind you leave on for a minute or two then rinse out). We used an inexpensive generic brand without a strong scent (Suave).
  • 3 Tablespoons Eucalyptus oil
  • 1/2 cup baby oil
  • Enough water to fill the remainder of a 32-ounce spray bottle

Ingredients for homemade horse fly sprayInstructions
Mix the ingredients in a 32 ounce spray bottle. Shake well before every use and spray the horse.

The Results
Like recipe #1, above, this homemade horse fly spray worked well around the barn and house but was of no help in the pasture for deer flies.

How Long It Lasted
Also like recipe #1, above, this fly spray lasted between 45 minutes and an hour.

Our Opinion
While this recipe worked about the same as recipe #1 it has more ingredients to purchase and mix, so is therefore slightly more complicated to make. We also didn’t like trying to get 1/2 cup of thick hair conditioner out of a measuring cup and into the top of the spray bottle. The conditioner kept plugging up the top of the bottle and using a kitchen funnel wasn’t much help. Since this recipe worked about the same as recipe #1, we prefer recipe #1 because it has fewer ingredients and is easier to mix.


Homemade Horse Fly Spray Recipe #3


Homemade essential oil horse fly spray

  • 12 ounces of water (after first putting the above ingredients into a spray bottle, this is enough water to fill the bottle to the 16 ounce line)

Note: Coconut oil is a liquid in hot summer temperatures (above 76 degrees Fahrenheit). In cooler temperatures, it is a solid. Therefore, coconut oil may not be suitable for a fly spray recipe unless the temperatures are warm.

Put all of the essential oils and the coconut oil into a spray bottle. Add enough water (which should be about 12 ounces) to fill the spray bottle to the 16 ounce line. Shake vigorously before every use, and occasionally during use. This mixture separates very easily.

Since essential oils can cause skin irritation, the first thing we did with this fly spray recipe was sprayed our own forearms and wait 24 hours. When we didn’t have any kind of skin irritation we tested it on the horse.

The Results 
Epic fail. Unlike with the other homemade fly spray recipes on this page we never even got the horse groomed or saddled before this recipe failed. We sprayed him, and there was a brief pause when he was really damp that the flies and other insects slowed down for a few moments. Then, after mere moments, he went back to fighting flies as if nothing at all had been sprayed on him. We had to follow with a different fly spray in order to groom and ride him.

With this “fly spray” recipe, if you can call it that, our horse did smell heavenly, but as an insect repellentthis homemade recipe was totally useless.

How Long It Lasted
Mere moments.

Our Opinion
This recipe is a total waste of essential oils and coconut oil. We like essential oils for some things, and love coconut oil as a mane and tail conditioner and homemade hoof conditioner, but when used together in this recipe as a fly repellent for our horses they didn’t work at all.


Homemade Horse Fly Spray Recipe #4

This is actually a semi-homemade fly spray recipe that is NOT all natural since one of the two ingredients is store-bought horse fly spray.


  • 1 part white vinegar
  • 1 part store-bought horse fly spay (we used a brand that had permethrin .25% as its active ingredient)

Vinegar and fly sprayInstructions
Mix equal amounts of white vinegar and store-bought fly spray in a spray bottle. Shake well before every use and spray the horse.

The Results
We feel like this semi-homemade fly spray recipe worked just as well to keep house and stable flies from biting our horse as when the store-bought fly spray was used alone. In fact, though it was hard to tell for sure, we thought it may even have worked slightly better. Although flies still landed on the horse the actual bites were greatly reduced.

When it came to deer flies, the mixture of vinegar and store-bought fly spray was helpful to keep them from biting the horse, but not as helpful as we had hoped. However, when the store-bought fly spray was used alone the results were only marginally better. In both cases deer flies still bit the horse in noticeable numbers, but slightly less than when no fly spray was used at all.

How Long It Lasted
This semi-homemade fly spray lasted about an hour, perhaps a little less. This is about the same amount of time the store-bought fly spray lasted when it was used by itself.

Our Opinion
In our opinion, the mixture of white vinegar and store-bought fly spray worked just as well for house, stable, and deer flies as when the store-bought fly spray was used alone. The mixture also lasted about the same amount of time, and since vinegar costs quite a bit less than store-bought fly spray using the mixture cut our costs significantly.


In Conclusion

For House And Stable Flies
Each of the homemade or semi-homemade horse fly spray recipes on this page – except for recipe #3 – worked well for us for house and stable flies. None of them were perfect – we still saw flies landing on the horse but the actual bites the horse received were greatly reduced. In our opinion the homemade recipes worked as well as the inexpensive brands of store-bought fly sprays we had recently tried and lasted about the same amount of time. They also have the advantage of being less expensive to use than higher priced store-bought sprays. Recipe #3 did not work at all.

For Deer Flies
None of the homemade or semi-homemade horse fly recipes we tested got a passing grade for deer flies. Recipe #1 and #2 were an out-an-out failure for deer flies, recipe #3 was an out-an-out failure for everything, and while recipe #4 worked better than nothing we still felt it left a lot to be desired.

Eucalyptus Oil – Fun Stuff To Know

Two of the natural homemade horse fly spray recipes above call for Eucalyptus oil as an ingredient. So, just what is Eucalyptus oil? Eucalyptus oil is an “essential oil,” which means it is a concentrated liquid derived from a plant, and that the liquid possesses the odor or flavor of the plant it comes from. In other words, essential oils contain the “essence” of the plants they are made from. Essential oils are sometimes called “volatile” or “ethereal” oils, or they might be called the “oil of” followed by the name of the plant they were made from.

The Eucalyptus oil we used in the recipes on this page was the oil of Eucalyptus globulus. Of the different species of Eucalyptus trees, Eucalyptus globulus is the kind most commonly used for the production of Eucalyptus oil. We bought an 8 ounce bottle of it from an eBay seller for a reasonable price that included shipping.