Are your dogs on medication to prevent heartworm and flea and tick infestation? DE (food/horticultural grade only) CAN be put on your dog, just be careful that no one breathes in the dust while airborne. The stuff can be eaten (literally), but not inhaled.

Have you considered nematodes as a control for your fleas? I have had some very good reports regarding this type of bio-control, when used properly.

There are also growth regulators for fleas that can be mixed in water and applied as a spray to the yard, bedding, and even inside the home. I have attached a link that might be helpful.

Fleas are a health problem for you as well as your dogs, so getting a handle on the population is important.

Here is a link that might be useful: Growth regulators

I have been using brewer's yeast tablets flavored with garlic for all three of my dogs and not one flea has been spotted so far. They are a flavored chewable tablet that can be mixed in food or given as a treat, most dogs love the taste. (Do a web search or check your local pet supply store for the tablets. I think some companies even make a powdered formula that you can sprinkle on their food, but I have never tried that.)

I do beleive that it takes some time for the brewer's yeast/garlic to build up in their system before it starts repelling fleas, but it may be something you wish to consider after you get the problem under control. (As an added bonus it also conditions their skin and coat.)

I'm not sure if you will be able to find an organic product, but it may be worth some searching.

Good Luck!

I'm not at all sure that the products sold by vets are good for our pets. At our farmer's market, an avocado farmer told me to add a small amount (1 tsp) of vinegar to a pet's water to control fleas and itching. I also read on the internet that it will change the ph of the animal's urine and help eliminate yellow spots on the lawn. I'm adding a small amount of apple cider vinegar to my dog's water each day and he doesn't seem to mind. Good luck.

1 tsp added to how much water? A cup? A gallon?

Sorry, but vinegar wouldn't do a darned thing to control a flea infestation. Fleas are a MAJOR health issue for our pests and for the loving owners of pest. A 'bad' infestation needs to be addressed with measures that work.