Try cedar chips. Fleas are repulsed by cedar chips because they hate the smell and will do their very best to avoid it. Go to the garden store and get two large 0.5 cubic ft bags of cedar chips and sprinkle it throughout the areas where the dogs will be.

Do fleas like cedar mulch?

Cedar mulch repels Fleas and Ticks. Use it to border areas where your pet likes to play or rest to keep insects from migrating into those areas. Place cedar mulch along the edges of your yard to form a barrier.

What type of cedar repels fleas?

Cedar Oil and Fleas Cedrus, Thuja and Juniperus species all contain the essential oil (called thujone) that repels insects.