It works when it's dry.

Diamotaceous Earth should not be watered in since it looses its effectiveness when wet.

No, do not water it in. The dog will be fine. The danger is when it becomes airborne when you are applying it. You can ue it outside as well as in your carpets and in any crevices in your house where the fleas like to hide. You can also use it on the dog's coat and it's much safer than the systemic flea control which is basically poison.

Many people also have a lot of success applying beneficial nematodes outside to eat the flea larvae. If you go that route, do not apply the DE to the same area.

Please, also remember to use only FOOD GRADE DE. very important! The pool filter version does not work and is toxic.

There is also a complany called fleabusters that uses a combo or boric acid and DE to get rid of fleas.

Ania

Sunnyside: I have three dogs and confine them to their yard and then if they are out walking and exposed to other dogs or lawns we use a dilute essential oil product in the fur (on the dog) to keep repelling stray fleas because an infestation is miserable when it occurs. We used a food grade diatamatous earth product from our local garden store when we did experience an infestation due to a friend's dog who visited. Now I do not let other dogs in my yard unless I know they are flea free as a rule. We also have planted mint and other herbs the dogs rub against when they come into the house. I did use team mule borax in my carpets as well, then vacum up and also use a mask. We also use cedar chips on paths where the dogs run. We no longer ever have fleas.