Best fly spray for horse flies

[Supertrooper]

I hate horse flies, poor horse was being driven mad by them and unfortunately my homemade fly spray wasn't touching them so do you have any recommendations pls xx

 

[Kaylum]

I make my own and only use citronella and water. It works on all ours. How much citronella are you putting in?

 

[Supertrooper]

I've been using white wine vinegar, squeeze of washing up liq, tea tree and lavender xx

 

[Bluejazz]

I use Karen Ruggles product which was called Stop it all, now called Ruggle It. Not cheap but it does work and the oil will last an whole summer. Great natural product. Used it for 3yrs