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How to Apply Diatomaceous Earth for Roaches and Bugs: Does it Work?

I have been using different roach-killing products for the past few years and regularly assess them based on their effectiveness, price, ease of use, and safety profile. But, of course, every product has its pros and cons. For example, insecticide spray is easy to use but not safe for pets and children. Similarly, Gel bait is very effective but messy and slow.

Follow these steps to apply diatomaceous earth for roaches and bugs,

  1. Select the appropriate type of diatomaceous earth.
  2. Select the best locations for applying diatomaceous earth.
  3. Dry and clean the area before applications because diatomaceous earth fails to work around water and moisture.
  4. Set up roach attractants in order to attract roaches to walk over diatomaceous earth.
  5. Apply a thin layer of Diatomaceous earth
  6. Regularly Observe and Repeat application if needed
  7. Clean the Mess to avoid inhalation

I have been using diatomaceous earth for roaches in one of my friend’s houses for the past month. I will be sharing the complete details, including its effectiveness, and giving my personal opinion about whether the hype surrounding this product is legit or just a product sale gimmick.

Before you read further, just a quick question. Tired of cockroaches and looking for a permanent solution?

Stop wasting your time, invest in these products and follow this guide: How to get rid of roaches? You will be roach-free in 10-20 days.

1. Max Force Glue Traps
2. Advion Gel Baits
3. Harris Powder Bait
4. Gentrol Insect Growth Regulator
5. Loctite Foam Sealent


Optional Items
1. Gel Bait Professional Gun
2. Torch
3. Powder Bait Puffer
4. Insecticide Spray to kill a reveled colony in a single shot

What is Diatomaceous Earth

Diatomaceous earth is a fine white abrasive powder made by grinding the remains of single-celled organisms called diatoms. Diatom is a type of microscopic algae and is found in oceans, waterways, and even soil.

This tiny organism is deposited on the rocks for millions of years to form intricate layers. These layers are harvested and then ground into a fine powder that we use in various applications.

The typical composition of Diatomaceous earth consists of,

  1. 80–90% Silica (Sand)
  2. 2–4% Alumina (Clay Mineral)
  3. 0.5–2% Iron Oxide (Rust)

Types of Diatomaceous Earth

Diatomaceous earth has two types, depending upon the percentage of silica inside. The higher the silica, the more dangerous it gets for life.

1. Food Grade Diatomaceous Earth

It contains less than 2% silica making it very safe. Although inhalation must be avoided, you can even consume it, and it will not cause any health problems (Reference). Therefore, it is safe around pets and children.

On the other hand, you will be happy to know that food-grade diatomaceous earth is lethal for pests, including roaches, ants, battles, and other bugs.

2. Filter Grade Diatomaceous Earth

It is called filter grade because it is used to filter water bodies such as swimming pools. This is because it contains around 60% Silica that acts as microscopic sieves that helps filter microscopic impurities.

Although Filter Grade Diatomaceous earth is very effective at killing roaches and bugs, it is hazardous because it can cause lung diseases, including cancer (Reference).

Do you know the biggest cockroaches measure more than 3 inches in size?

Is Diatomaceous Earth effective Against Roaches?

Diatomaceous earth is a fine white abrasive powder that kills insects, including roaches, and is very safe to use. It is easily available online and in stores.

However, diatomaceous earth for killing roaches is slow, time-consuming, messy not entirely effective as claimed.

In addition, the product loses its efficacy in moisture or on contacting water. On a scale from 1 to 10, I rate a gel bait 8 and diatomaceous earth 5.5

Moreover, diatomaceous earth should not be used outside the house for killing roaches because it loses its killing power on contacting the soil.

How Diatomaceous Earth works Against Cockroaches?

Diatomaceous earth acts like microscopic needles when used to kill roaches and bugs once you spread it on surfaces, the DE tricky roaches into walking on them.

After the roaches walk past the diatomaceous earth, it sticks to the body of roaches, bugs, and insects and punctures it. Slowly the pests die of dehydration and injury within the next few days. The results of DE are slow; it takes between 15 days to a month before you will start to see a reduction in the roach population.

Do you know your peanut butter contains bugs? Read this article to know more.

How to Apply diatomaceous earth for roaches

When diatomaceous earth is applied correctly, it shows better results in getting rid of roaches. However, as mentioned earlier do not expect miraculous results with diatomaceous earth because my personal experience showed borderline results.

Here is how to apply diatomaceous earth for roaches: Stepwise,

Step 1: Select the appropriate type of DE

For diatomaceous earth to work best, you need to buy the best safety product. Every manufacturer claims its DE to be the best; however, the quality of Diatomaceous earth strictly depends on how it is ground into fine powder.

I used three products from amazon, and the best was HARRIS Diatomaceous Earth Food Grade. It also came with an applicator for easy access to cracks and crevices.

Step 2: Select the best Locations for DE Application

It is no joke that you will apply Diatomaceous earth anywhere, and it will work. If you failed to select proper locations, do not expect results.

I have written a complete article on Where do Roaches Hide? [Solved With Pictures] to help you apply diatomaceous earth or any other roach-killing product. Please read this article before applying.

Step 3: Clean the Area

Diatomaceous earth only works when it’s dry. Once the DE absorbs water, the abrasive power of powder is immediately lost and fails to work.

Therefore, it is crucial to clean the area and make sure it’s dry. If the area can’t be kept dry, for example, in an area with active seeping water, try alternative methods to kill roaches.

Step 4: Set up roach attractants

For the Diatomaceous earth to work fast, you need to set up traps that attract roaches. For example, you can keep a rotting fruit or a piece of cheese to attract them more. This way, they will cross the DE powder and get killed.

Step 5: Regularly Observe

Regularly observe the quality of sprinkled DE product for moisture content. If the Diatomaceous earth is wet, replace it with a new one. It would help if you kept repeating it for a month to be effective.

This is also why I do not prefer the use of DE.

Step 6: Clean the Mess

Once you have gained satisfactory results, do not forget to clean the mess. This is because the dead cockroach attracts more roaches and can cause disease and trigger allergies.

Moreover, long-term use of DE is associated with inhalational injury.

Which is better boric acid or diatomaceous earth?

Boric acid is an odorless and colorless crystal or white powder with weak acidic properties. It is often used as an insecticide, antiseptic, and flame retardant.

Boric acid has excellent killing power against roaches and has been used for centuries. The good thing about boric acid is that it stays on the surface for a long and effectively keeps on killing roaches.

However, boric acid must be consumed by roaches in order to kill them. Therefore it must be mixed with a substitute like flour or sugar.

On the other hand, diatomaceous earth kills roaches by puncturing them and needs not be consumed by roaches but is less effective.

However, when speaking about effectiveness, Boric acid is far superior to diatomaceous earth in killing roaches.

FactorsBoric AcidDiatomaceous earth
Effectiveness86
Ease of Use65
Safety68
Availability Easily Available Easily Available
PriceLess ExpensiveMore Expensive
FormsTablets, Gels, PowderPowder Only
Comparison between Boric acid and Diatomaceous Earth (out of 10)

Caution while using Diatomaceous earth

Diatomaceous earth is known to cause inhalational injury no matter what type it belongs to. However, inhalational injury with Filter Grade is far more than food Grade Diatomaceous earth.

Therefore you must keep following precautions when using Diatomaceous earth,

  1. Never Use Filter Grade DE, only use food grade
  2. When applying diatomaceous earth for roaches, wear a mask
  3. Never use high power fan near the sprinkled DE
  4. Regularly check the powder and do not use it for more than a month without taking a break.
  5. Look for the signs of inhalation injury or allergy (Cough, Nasal irritation, Sneezing, Shortness of Breath) Immediately consult a registered medical practitioner.

Additional Read!