How Long Does Diatomaceous Earth Take to Kill Fleas?

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Diatomaceous earth is a popular pest control product that has circulated the internet for years. But a lot of people still haven’t gotten the full picture when it comes to this flea treatment. For starters, how long does diatomaceous earth take to kill fleas? Is this product safe? Or are there some side effects that most homeowners just brush off?

Read on for the answers of the most commonly asked questions about this flea killer.

How Long Does Diatomaceous Earth Take to Kill Fleas?

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Diatomaceous earth is lethal to fleas, but it’s safe and environmentally friendly. CC Image courtesy of SprocketRocket and Luis Fernández García on Wikipedia

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What’s diatomaceous earth?

Diatomaceous earth or diatomite is a natural occurring sediment that comes from the fossils of diatoms, a kind of algae that died millions of years ago.

It’s a powdery white substance that looks like flour. But don’t let this fool you. It’s actually abrasive in nature. That’s because it’s made from a combination of silica, alumina and iron oxide.

Diatomaceous earth is commonly known as a pesticide, but it also has its uses in making skin care products, toothpastes, water filters and pet supplements.

You can find D.E. on your local garden shops or in any supermarket. They’re usually very cheap, and they come in two kinds, food grade and pool grade.

Why do you have to use “food grade” diatomaceous earth?

The names of the two kinds of diatomaceous earth products tell exactly what they’re for.

According to Absorbent Products LTD, food grade D.E. does what it’s named for. It’s edible. It’s safe for both humans and animals to consume because it has passed careful inspections and testing to have safe and minute levels of arsenic, lead and silica, substances that you can find a lot in raw unprocessed diatomaceous earth.

On the other hand, pool grade D.E. is ONLY used for pool water filtration. It’s been treated with extremely high heat, so it contains high levels of crystalline silica, a material that’s toxic to humans and pets.

Remember that you can’t substitute pool grade D.E. for the other. Read the labels carefully before using any type of D.E.

How do you use food grade diatomaceous earth?

Using diatomaceous earth is just like using borax. Here’s how you should do it:

  • Vacuum the area you’re going to treat. Vacuuming clears out unwanted debris, flea eggs, larvae and even some adult fleas. Also, the vibrations caused by vacuuming forces flea pupas to “wake up” from their dormant stage and spring out. This gives you the advantage of killing even more fleas since hiding in pupa shells make them less susceptible to treatments.
  • Make sure the area being treated is dry. Wet surfaces make D.E. less effective.
  • Wear goggles and a mask. D.E. can cause irritation to your eyes, nose and throat if you’re exposed to a substantial amount of it. (Read more on this below.)
  • Sprinkle food grade D.E. Sprinkle a generous amount of diatomaceous earth on your carpet, bedding, furniture, upholstery and even on your yard.
  • Do this 2 times a week. Don’t just do this treatment once. Apply the diatomaceous earth 2 times a week. This way, you’re not giving fleas any time to recover.​

How long does diatomaceous earth take to kill fleas?

Diatomaceous earth takes a while to kill off fleas.

What it does is that its sharp particles puncture the fleas’ waxy exoskeletons and enter their insides. Once in, the powder sucks all the moisture out of the insects’ bodies and dehydrates them to death.

For this to happen, you have to wait for a couple of hours for fleas to make direct contact with the powder. That can take a while, but you usually see results about 12 hours after you’ve applied the treatment.

We recommend leaving the D.E. on a surface for 1 to 2 days to get rid of as much fleas as you can.

Is diatomaceous earth effective?

Unlike other flea killers, D.E. is backed up by published scientific studies, proving the effectiveness of this treatment in different cases.

One study from the Journal of Field Ornithology revealed that continuously sprinkling just a thin layer of the powder in a nest of swallows for over 2 years almost completely wiped out its flea population.

Another study from the Poultry Science journal concluded that hens which had diatomaceous earth in their diets dealt with less internal parasites and mites.

So if you’ve ever wondered if D.E. delivers what success stories claim, some scientists have already answered your question for you.

Is it safe for kids and pets?

Generally, food grade diatomaceous earth is safe around kids and pets. You can even include this powder in their diets, provided that you’ve consulted a doctor or a vet first.

However, there are some small warnings that you have to remember about this product.

  • It dries out your skin. This isn’t such a big deal. But if you have someone in your household with sensitive skin, it’s best to keep him out of the treatment area.
  • Some people can’t tell the difference between pool grade and food grade. Just remember that the first one is highly toxic and dangerous. Don’t skip on reading the labels.
  • It’s also not friendly towards our eyes. Since it can irritate our skin, it stands to reason that it’s abrasive properties will also cause redness to your eyes.
  • It can irritate your nose and throat as well. According to the National Pesticide Information Center, diatomaceous earth can cause some degree of irritation to your nose and nasal passages if you’ve inhaled a lot of it. You can also experience shortness of breath and coughing.

So there you have it, everything important you need to know about D.E., including the answer to the question “How long does diatomaceous earth take to kill fleas?”.

Hopefully, this article answered most of your questions on the product, and it has fully convinced you to give this inexpensive treatment a try.