How to Spread Diatomaceous Earth on Your Lawn [7 Steps]

To properly spread diatomaceous earth in your yard, first, pinpoint areas of insect infestation. These are the areas that should be treated with diatomaceous earth. Then, spread diatomaceous earth on a windless day. Make sure to use food-grade diatomaceous earth only and always wear breath protection to avoid inhaling airborne diatomaceous earth powder. Spread your powdered diatomaceous earth in a circle around problem areas. Then, spray a liquid solution of diatomaceous earth at garden edges and near garbage cans. Finally, reapply diatomaceous earth when the ground dries after rain.

7 Steps to Spread Diatomaceous Earth On Your Lawn

Diatomaceous earth (DE for short) is made of the fossilized remains of single-celled organisms. This results in a fine powder of sharp particles. These particles kill many common lawn and garden pests easily, but won’t harm people, pets, or plants. To spread this all-natural pest control powder, use these tips:

Locate Areas That Need to Be Treated

When using diatomaceous earth, it’s essential to treat only areas where pests have invaded your yard. Look for ant mounds and use the right method when killing ants with diatomaceous earth. Other areas that need to be treated with diatomaceous earth are locations where slugs, snails, ants, and other insects have attacked your plants. If aphids and slugs are attacking your garden plants, plan to use diatomaceous earth to protect them.

• Look for ant mounds and damaged garden plants in your yard.
• Plan to spread a ring of diatomaceous earth around these problem areas.
• Do not spread diatomaceous earth through your entire yard.
• Diatomaceous earth works best when concentrated in specific areas.

It’s not wise to spread diatomaceous earth throughout your entire yard. Doing so can kill pollinators and helpful insects. Instead, plan to spread rings of diatomaceous earth around problem areas so that any pests that try to pass through the ring will crawl through the powder, which will kill the pests. 

Choose a Wind-Free Day

Pick a day with little to no wind if you’re spreading diatomaceous earth. Windy days can blow away your diatomaceous earth powder. This will render your powder application useless. Remember, it requires a thick application of diatomaceous earth to kill insects that pass through it. If the wind blows away your DE, it won’t do much good.

• Make sure there is little or no wind on the day you spread your diatomaceous earth.
• Wind can blow away your DE powder, making it ineffective.
• If you spread diatomaceous earth on a windy day, it may be blown back into your eyes.

Choosing a wind-free day also lowers the risk of diatomaceous earth blowing back into your eyes. Although food-grade diatomaceous earth is safe for humans and animals, the tiny diatom fossils are sharp and can cause eye irritation.

Use Food-Quality Diatomaceous Earth

Food-grade diatomaceous earth is safe for use in your yard and will not harm your pets or your family. Pool-grade diatomaceous earth is not safe for use in your yard because it is actually toxic to people and animals. Use only food-grade DE when treating your yard and garden.

• Food-grade diatomaceous earth is safe for people, plants, pets.
• Pool-grade diatomaceous earth is not safe for people and pets and should not be used to treat your yard.
• This human and pet-safe diatomaceous earth can be safely used in your yard.

Make sure any diatomaceous earth you purchase is clearly labeled as “food-grade.” Doing so will protect your family and any animals that venture into your yard.

Wear Protective Gear

Inhaling diatomaceous earth powder can irritate your eyes, nasal lining, and airways. Be sure to wear a dust mask and safety goggles. While the abrasive particles in DE are not dangerous to humans, it’s still unpleasant to get them in your eyes and lungs.

• Use these combination safety goggles and face shield to protect yourself while applying DE powder.
• Inhaling DE, or getting it in your eyes, can cause irritation.
• Even though inhaling food-grade DE isn’t dangerous, it is not pleasant.

By using food-quality diatomaceous earth and wearing proper protection when you apply it to your yard, you will remain completely safe. This makes DE one of the safest pest control substances on the market.

Spread Diatomaceous Earth

Pour a ring of diatomaceous earth around ant mounds and plants that have been attacked by insects. The ring should be clearly visible on your lawn. It should be 3–4 inches (7.5–10 cm) wide in a halo around the ant colony or plant. You can pour straight from the bag, or you can use a sifter.

• Spread diatomaceous earth in a ring around ant mounds and garden plants.
• Consider pouring a border of diatomaceous earth around your garden to keep slugs, snails, and aphids out.
• Any pest that crawls through DE powder will be killed.

By spreading a ring of diatomaceous earth, you create a barrier that kills any insects or pests that attempt to pass through the DE. Ants that try to leave a mound surrounded by a ring of diatomaceous earth will die as they attempt to pass through the ring of DE powder. Similarly, any aphids, snails, and slugs that try to crawl through diatomaceous earth to attack your garden will become dehydrated and die.

Try the Wet Application Method

Add 4 tablespoons (60 ml) of diatomaceous earth to 1 gallon (3.8 liters) of water. Stir this mixture together until the powdery diatomaceous earth fully dissolves. Then, fill a spray bottle or garden sprayer with this mixture and spray liberally around ant mounds or along garden borders. This method helps apply diatomaceous earth to hard-to-reach places.

• Mix diatomaceous earth with water to make your own diatomaceous earth spray.
• 4 tablespoons (60 ml) of diatomaceous earth dissolved in 1 gallon (3.8 liters) of water creates a sprayable mix.
• Spray diatomaceous earth along garden edges or around ant mounds to kill pests.

A liquid mixture of diatomaceous earth becomes active when it dries. Any ants or other insects that walk or crawl through the dried mixture will die. It’s a great idea to use both the dry and wet application methods. Pour a ring of dry diatomaceous earth around ant colonies and pest-damaged plants. Then, spray liquid diatomaceous earth along ant trails, slug trails, garbage cans, and near crevices around doors.

Reapply After Rain

Diatomaceous earth is washed away by rain. It can also be washed away if you water your lawn and garden with a sprinkler system. So, pay close attention to the weather and your watering schedules. It’s likely that any significant rainfall will wash away your application of DE.

• Rainfall and watering with a sprinkler will wash away diatomaceous earth applications.
• Allow your yard to dry after it has become wet, then reapply your DE.
• Diatomaceous earth is not effective in wet conditions.

After your yard has been soaked, allow your lawn and garden to fully dry. Then, repeat the previous steps to apply new diatomaceous earth. This way, you ensure all-around protection for your plants.

How Often Should You Apply Diatomaceous Earth to Your Lawn?

Diatomaceous earth is generally most effective when applied once every 3–4 weeks. This is because routine lawn care like watering your lawn can wash away the powder. Even if you don’t water regularly, morning dew can dilute your diatomaceous earth application over time.

• Apply diatomaceous earth powder once a month for best results.
• Reapply DE after heavy rains or strong winds—both of these can clear the powder from your lawn.

You should also reapply diatomaceous earth after a storm or any period of heavy rainfall. This also goes for periods of strong winds. Because it is a fine dust, DE can be washed or blown away fairly quickly.

Does Diatomaceous Earth Still Work if It Gets Wet?

Wet diatomaceous earth does not kill any pests, unfortunately. So, if it rains or you water your lawn, you’ll temporarily lose its preventative power. However, diatomaceous earth dries out pretty quickly and will be effective again once all the moisture has evaporated.

• Diatomaceous earth is ineffective while wet.
• DE will regain its effectiveness once it dries, as long as it has not been washed away.
• If your DE has been washed away, repeat your application.

Be sure to reapply diatomaceous earth after heavy rainfall or strong winds. This will help keep your lawn well protected and minimize the risk of the powder being blown or washed away.

How Do You Apply Diatomaceous Earth to Soil?

Diatomaceous earth is a very effective form of pest control. It is safe for children, pets, and wild animals while still killing unwanted pests like slugs and ants. In order to use it in your yard, follow these steps:

• Do not plan to apply diatomaceous earth to your entire yard.
• Pinpoint problem areas such as ant mounds and garden plants that have been attacked by pests.
• Spread diatomaceous earth on a windless day.
• Use food-grade diatomaceous earth only—never use pool-grade diatomaceous earth in your yard.
• Wear eye and breath protection when spreading diatomaceous earth.
• Spread a ring of diatomaceous earth around ant colonies and pest-attacked plants.
• Spray a mixture of diatomaceous earth and water along garden borders and around garbage cans to kill additional pests.
• Reapply diatomaceous earth after rainfall or lawn watering.

By using these steps, you’ll apply diatomaceous earth to your lawn safely. This natural, chemical-free powder can kill ants, slugs, and other invasive insects quickly. Your garden and lawn will flourish with the correct use of diatomaceous earth.