If your dog has spinosad in their bloodstream before a flea tries to take a bite out of them, it will kill the fleas before they can lay eggs. Natural Flea Treatments for. To make a natural flea dip, start by steeping two cups of fresh rosemary in boiling water for 30 minutes. Strain the liquid, throw away the remaining. Sprinkle powdered sulfur on your grass, shrubs, and other outdoor places where your pet hangs out. It's not harmful to humans. But it can be toxic or even deadly. If your dog has a short or slick coat, you can also use a cloth dipped in the juice instead of a comb. If your dog has spinosad in their bloodstream is there a home remedy for fleas on dogs a flea tries to take a bite out of them, it will kill the fleas before they can lay eggs. That being said, some—including rosemary, peppermint and highly diluted tea-tree oils—are very effective flea remedies. Bob Goldstein, this collar is infused with herbs and essential oils to naturally repel fleas and ticks. Note, this shampoo is not meant to address a flea infection, we suggest the TropiClean Maximum Strength formulation, seen above, for that. Salt Much like baking soda, salt is a great natural flea home remedy when accompanied by vacuuming. No matter how big your dog is, I prefer not to give more than two cloves of garlic per day.