Essential oils are well-researched for their role in repelling pests. Some of the most effective oils include turmeric, cedar, lavender, lemongrass and geranium. Our homemade essential oil spray recipes are easy to make, store and carry. Dogs have extremely sensitive noses and skin so start with a small amount sprayed on a bandana. Alternatively, spray your hands and gently rub through your dog’s fur, avoiding her nose, eyes, mouth and genitals.