Several herbs repel flies. Use squares of cheesecloth to make sachets of crushed mint or basil. Another sachet can be made from bay leaves, cloves and eucalyptus. Hang sachets near open windows or place them around your home. A pot of basil will also help repel flies, if placed on the windowsill. Basil will smell stronger, and be more effective, if you water it from the bottom.
Mix the yolk of an egg with 1 tsp. each of molasses and black pepper. Pour the mixture into a shallow dish and leave it out to kill flies. Another option is to scratch an orange skin and stud it with cloves. Flies will be repelled by the scent.
Place a few drops of eucalyptus oil on a piece of cloth and leave it wherever flies are a problem. Oil of cloves, lemon, juniper, pine, lavender and geranium will all repel flies. Placing the oil in a diffuser can help distribute the fragrance but if you don’t have one, put a few drops of oil on a sponge or absorbent cloth and set it on a saucer.
Boil sugar, corn syrup and water together and spread the mixture on brown paper. You can hang this flypaper by poking a hole in the top and threading it with string. You can also make flypaper by mixing 1/4 cup of syrup with 1 tbsp. each of granulated and brown sugar. This recipe doesn’t need to be cooked. Soak strips of brown paper in the mixture and let them dry before hanging.
Borax can be used in several ways to help deter flies. Sprinkle it in your garbage can, either by itself or mixed with food-grade diatomaceous earth. You can also mix borax and diatomaceous earth with syrup or honey to make an even more appealing trap. Borax and diatomaceous earth can be dangerous to pets and children as they can be toxic if ingested, so use with care.
A dish with some soap bubbles in it will attract and kill flies. You can also make a repellent by mixing dish soap, vinegar and water and using it in a spray container.