Back in the day, there were lots of perfectly good folk remedies for keeping fleas off the dog, and out of the house, off the kids, and off of you.
Here are some of them -- personally, I've used the garlic remedy for over 14 years now, with no problem (some will say garlic is bad for dogs -- mine, all lab mixes, have never had a complaint). I do more than just the garlic, though: I combine several of these remedies, and we never have a flea problem.
1. Apple Cider Vinegar - 1 T in the dog's water bowl. Fleas don't like the smell.
2. Brewer's Yeast Tablets - fed to the dog, the yeast makes the skin uninviting to fleas.
3. Garlic - I put fresh garlic into the homemade dog food, others give their dogs a clove each day. However you think best, it's another smell-repellent.
4. Omega 3 and Omega 6 Fatty Acid Supplements - Omega 3 (flax seed tablets, salmon, sardines) or Omega 6 (sunflower oil, safflower oil, wheatgerm oil, evening primrose oil). Feed them sardines, put oil in their food, or give them supplements.
5. Homemade Flea Collar - take a rope or cloth collar and thoroughly rub into it one of the following: tea tree oil, lavender oil, eucalyptus oil. Do this WEEKLY.
6. Dog Spray -- combine boiling water with a couple of quartered lemons. Let it set for a day or two. Spray on the dog, particular the vulnerable spots (armpits, tummy).
7. Salt Water Baths -- dogs near the ocean have it made; salt water baths are a great flea preventative.
8. Thorough cleaning of the dog bed, frequent vacuuming of the home, and bathing of the pets are great helps.
Personally, I put garlic in the homemade dog food, and apple cider vinegar in the water periodically. The dogs get bathed, and the floors get vacuumed frequently. I use the new Febreze Allergen Reducer spray on the mattress as well as the den furniture (the dog areas) and I think this helps, too. Yes, fine. The dogs sleep on the bed. I admit it.
Sources: www.doggienews.com; www.motherearthnews.com; www.dogfoodproject.com; www.peteducation.com