Flea control is challenging, even for professional exterminators. This is one pest that you may want to consider hiring a professional PCO to handle. But whether you decide to hire a pro or do it yourself (more about that later), the most important part of effective flea control is preparation.
Prior to the exterminator arriving (or prior to doing it yourself), you should prepare for the flea control job by taking the following steps:
All bedding, slipcovers, pet bedding, and similar items should be dry cleaned or washed in detergent and the hottest water the fabric can stand, and then tumble dried. If at all possible, store the freshly washed-and-dried articles in airtight storage containers in a place that's not infested with fleas until after the flea treatment.
Remove as much stuff as possible from the floor and store it elsewhere or stack it on tables to provide maximum access to the floor for treatment.
All carpeting and upholstered furniture should be thoroughly vacuumed and shampooed using products that do not contain stain repellents (which can interfere with subsequent insecticide treatments). Kleen Free Naturally would be an excellent choice. Wooden flooring that contains gaps between the tiles or slats should be also be methodically vacuumed and washed. Allow carpeting, furniture, and flooring to dry before performing the flea treatment.
Thoroughly clean the interior of your car(s), as well, especially if your pet(s) ride in the vehicle(s).
Pets should receive professional flea treatments or be treated with a high-quality flea shampoo at the same time (or as close as possible) to when the house is treated, and kept out of the house until the products used inside the house are thoroughly dried. This is to prevent fleas in the house from re-infesting the pet, and vice-versa. As with all pesticides, be sure to read, understand, and follow the label instructions, including making sure that your kind of pet (dog, cat, ferret, etc.) is listed on the label.
There are several ways to treat a flea infestation, but the most common is to use a liquid flea spray that is labeled for fleas on all carpeting, floors, pet bedding areas, and cracks and crevices in wooden flooring and around baseboards. Upholstered furnishings, draperies, and other textiles must also be treated unless they can be washed and tumble dried. Most of these sprays contain "adulticides" to kill adult fleas, and some of the better ones also contain Precor, which is an insect growth regulator developed especially for flea control.
Unless the flea spray you choose already contains it, I suggest you also use Precor. It comes in liquid form that can be added to other liquid insecticides before spraying them, and in aerosols that can be applied as a separate treatment. Some people use only Precor without an adulticide. That will work, too, but usually will take much longer unless you manage to remove literally every adult flea by vacuuming and washing.
Some liquid insecticides come with a plastic pump- or trigger-type sprayer. I have found these to be completely useless for flea control. I throw them away and use a professional-quality compressed-air sprayer like the B&G N124-S-18 instead. For carpeting and upholstery, I use the flat-fan nozzle at a high-enough pressure to penetrate deep into the fabric or the pile of the carpet without saturating it.
Insecticide application rates vary by product, but rates of one gallon per every 800 to 1,000 square feet are common. When using liquid insecticides for flea control, thorough, even coverage is more essential than quantity.
The insecticide should be applied as per the label instructions, being careful to methodically treat all susceptible surfaces (carpeting, pet bedding, etc.). Again, this doesn't mean saturating the surfaces with insecticides. We're not trying to drown the fleas. Use the insecticide at the label-specified rates. Over-application is illegal, wasteful, will not improve the success of the treatment, and may be dangerous. But do apply the insecticide methodically and evenly, being careful to treat all susceptible areas in accordance with the label instructions.
Flea control carpet powders and crystals are useful for thick or shag carpeting that may be difficult to penetrate using liquids. They usually consist of a desiccant powder like silica gel or diatomaceous earth, with or without a toxicant like boric acid, pyrethrin, or a synthetic pyrethroid. Carpet powders are easy to use. Typically, they are sprinkled on and worked into the carpeting, and then vacuumed up after a specified period of time. Powders can be used by themselves or as ad adjunct to liquid treatments of upholstered furniture.
It's very difficult to eradicate a flea problem without using any pesticides at all. About the closest you can come would be doing repeated thorough vacuuming and shampooing of the floors, carpets, and upholstery with something like Kleen Free Naturally on a weekly basis until all the fleas are gone. Using a steam carpet cleaner with an upholstery attachment and a sufficient quantity of flea traps would improve your odds of a successful non-chemical treatment.
A middle-of-the-road approach would be to use a naturally-derived flea spray that contains no synthetic pesticides, or to treat the carpets with natural diatomaceous earth with no added toxicant. Diatomaceous earth has very sharp edges that cut and score insects' outer coatings and cause them to dehydrate. Used properly, it can be effective; but it's also very slow, and the treatment usually has to be repeated several times at weekly intervals.
I do have several cautions about using diatomaceous earth on carpeting or furniture. Firstly, although it's essentially non-toxic, it is a potent respiratory irritant. Use a respirator and dust mask when working with it. Secondly, its sharp edges will wear away at carpeting and furniture if it's not completely removed. That's easier said than done because it works its way into the fibers. Once your flea problem is solved, it's a good idea to re-clean the furniture and carpeting with a carpet and upholstery cleaning machine to remove as much of the powder as possible.
Remember that just as with any pesticide, be sure to follow the label instructions when using natural pest control products. "Natural" doesn't mean "hazard-free." Treat natural products with the same respect you would any pesticide.
There are many aerosol "foggers" labeled for flea control. Fogging comes with its own set of chemical, physical, and fire hazards. Furthermore, in our experience, fogging is rarely necessary except in very severe flea infestations. We strongly recommend that do-it-yourselfers avoid the use of aerosol fogs. If your flea problem is that severe, then you really need to call a professional.
We recommend taking your pet to a veterinarian or a licensed animal groomer to be treated for fleas. If you would prefer to do it yourself, however, there are a wide variety of flea shampoos and other flea control products to choose from. Be sure to follow all label instructions, and monitor your pet for any adverse reactions.
Related Page: Flea Biology