What naturally repels fleas from dogs?

Diatomaceous earth is a talc-like powder made from silica, the same stuff that makes up sand, and it kills fleas by drying them out. You can sprinkle it on carpets, bedding, and furniture. It’s safe and nonpoisonous, but like any dusty powder, it may irritate your airways if you breathe it in. Sulfur is a natural element that makes rotten eggs stink and also kills fleas that touch it or eat it by messing with their energy production. Sprinkle powdered sulfur on your grass, shrubs, and other outdoor places where your pet hangs out, but use it with care as it can be toxic or even deadly for your dog or cat if they eat too much of it. Extracts from citrus peels, like linalool or D-limonene, can work indoors to treat both fleas and their eggs, but read the label before you buy as some cats can have bad reactions to citrus peel extract. Borate powder is poisonous to fleas but safe for pets and humans, and you can sprinkle it into carpets and furniture, let it sit, and then vacuum it up. The oil from the pennyroyal plant can kill fleas, but it may not be a good choice for DIY sprays or other remedies as it can poison dogs and cats.