DIY Fly Spray Recipes for Horses

Use Common Ingredients to Protect Your Horse From Flies

A mosquito, close up.
Mosquitos carry disease that can make horses very sick. Image Credit:Frank Greenaway /Getty Images

About the time we're sighing with relief because winter is finally over, the pestiferous bugs show up, making life miserable for horse and human. Flies and biting insects aren't just a nuisance, they can carry some really serious diseases like Pigeon Fever, West Nile Virus and Equine Infectious Anemia. One of the most prolific crops on our hobby farm was the mosquitos. They were large and fierce, making the horses pace for hours.

Protecting horses from flying and biting insects can be can be a challenge. While you can purchase commercial fly sprays, many people prefer to make their own concoctions. Before you start mixing and spraying though, take some time to clean up your horse's stable and pastures with some natural pest control to simply reduce the number of bugs you're fighting.

Many horse owners start repelling insects from the inside out. Garlic is a favorite supplement that's felt to help control flies. A University of Guelph study found that excessive feeding of garlic was actually harmful to horses. The debate over whether garlic is safe for horses is ongoing. However, the small amount fed by most of us is generally considered safe and may help repel face and body flies. Cider vinegar is a common ingredient in many home-made fly sprays and feeding it is popular too. The vinegar is felt to make your horse less tasty to biting insects.

Cider vinegar can be added to the horse's feed, or in their water. It's often combined with crushed or powdered garlic.

Essential oils and herbs are often used in home made fly repellent preparations. I've had good results with lavender oil, and many people use eucalyptus and citronella oils. All are easily found in pharmacies, grocery stores and of course health food stores.

Pennyroyal is a common oil used in fly repellents, but it is toxic, so not a good choice for horses.

The Recipes

Face flies can make a horse really frantic, plus they can carry disease. Here's a fly repellent made for face flies.

This home recipe for keeping flies off a horse's face and body is from forum member zenagirl2727 . She recommends putting some in a small spray bottle and spraying the cloth and using that to apply it to the horse. Carry a cloth to reapply when needed.


  • 1 c. water


  • 2 c. apple cider vinegar


  • 1 c Avon Skin So Soft bath oil


  • 1 TBSP citronella oil


  • 1 TBSP. Eucalyptus oil

Mix this into a large spray bottle shake well  then and before applying to a cloth. Do not wipe around the top of the horse’s eyes since sweat may cause it to run down into their eyes and may irritate them. Furthermore, if you have pink skin on your horses face put a little sun screen on it and allow it to dry before putting the fly repellent on it.

A slight variation on this recipe comes from forum member ponyluver10

This spray attracts dust. So don't use it before a show.


  • 500ml (2 cups) light mineral oil


  • 125ml (1/2 cup) lemon juice


  • 10ml (2 tsp.) citronella oil


  • 10ml eucalyptus oil


  • 10ml lemon dish detergent


  • optional 125ml glycerine

Mix in a spray bottle and spray away!

She also recommends mixing seven parts water with one part citronella as a fly spray for a non-oily spray. Increase the water to four parts to one part citronella during the worst of the fly season.

Lavender Spray

Mix four parts vodka, grain alcohol or water to one part lavender oil. This also smells nice and works for a short time. Also nice to use as a relaxing room or linen spray. The alcohol mixtures dry faster than water, while leaving the fragrant oil behind.

Repelling Blackflies

Avon Skin So Soft is often recommended for fly control. I have found it to be very effective for blackflies in the spring. It’s not long lasting, so it has to be reapplied often. I use it on myself too. Just wipe it on with a cloth.

Don't Try This at Home

WD40 is sometimes recommended as a fly spray.

That's definitely not a use recommended by the manufacturer and I wouldn't want to put it on my horse's skin either. Dryer sheets are often recommended to repel flies, but I have not found them very effective. I also met a man who was quite proud of his diesel oil concoction, claiming that once applied, the bugs would stay away for days. I can't imagine I'd want to touch the horses either, and I don't want to think what effect it had on the horses themselves.