I see your in Minnesota, so you would not have the same plants we have in Florida. But if you want to experiment a little what I did is found some plants with bug repellent properties and started experimenting until I found a mix that worked. My favorite so far is using wax myrtle which has mosquito repellant qualities. I took the leaves and ground them in a food grinder, heated water and let them steep until the mixture cooled. Then strained the liquid, added aloe juice, a little apple cider vinegar as a preservative and had mosquito repellant. Now I am experimenting with different essential oils to repel flies, so far adding peppermint, encephalitis, and citronella seems effective for about two days. But it is a bit of a process the experimenting part.