How To Kill & Get Rid Of Fleas In The Yard

  • Written By Dan Edwards on June 28, 2018
    Last Updated: December 10, 2020

It can be daunting to deal with a flea infestation. These critters can appear almost anywhere in and around your home, including your yard. If you don’t target the flea population outside, it can restart an infestation inside.

I will illustrate how you can find out if you have fleas living in your yard. I will also cover the different techniques you can use to get rid of fleas outdoors. Most importantly, you will learn about the steps to take before, during and after getting rid of fleas in your yard.

How Do You Know If You Have Fleas in the Yard?

There are a few signs indicating that you may have a flea problem outdoors. Perhaps you have already treated your pet and your home for fleas, and the infestation has suddenly restarted again.

Fleas thrive in moist, humid environments. Fleas in the yard are more likely to be a problem during the summer months. If you live in a state with a warm climate most of the year, fleas can live in your yard almost anytime.

If you are consistently dealing with a flea-infested outdoor cat or dog every summer, fleas in the yard might be the culprit.

Fleas pass through four stages of development. Adult fleas tend to stick to the host, where the food supply is located. As female fleas need a meal prior to laying eggs, the eggs will likely be laid on your pet.

Flea Life Cycle Larva Stages

However, flea eggs, larvae, and pupae can be found anywhere your pet spends time, whether indoors or outdoors. The eggs are smooth rather than sticky, so once they are laid on your pet, they simply slip off.

Flea Egg
Flea Egg – CC Image courtesy of Russ Crutcher
flea eggs

When these eggs hatch, flea larvae will emerge. These worm-like creatures prefer dark areas, and will stay hidden for up to two weeks until they form a type of cocoon.

3rd Instar Cat Flea Larva
3rd Instar Cat Flea Larva
Flea Cocoon
Flea Encased In A Clear Cocoon (Pupae)

Unlike adult fleas, flea larvae do not need blood to survive. Instead, they consume debris such as skin cells that are found throughout their environment.

Although a freshly emerged adult flea needs to find a host rapidly or it will die, developed adult fleas can live for months without food. In fact, many fleas stay dormant until conditions are optimal.

This could be when they sense the presence of a host nearby or temperatures heat up. An example of a possible scenario: you return from vacation to a flea-free home and suddenly your outdoor cat is bringing in fleas.

Fleas can find their way into your yard. Wild animals such as raccoons or squirrels can harbor fleas, and reside underneath porches or decks.

If you discover the nest or home of a wild animal outside on your property, contact the appropriate authorities in your area before treating the yard. Do not attempt to remove the animal by yourself.

How to Find Fleas in the Yard

Open areas that are directly exposed to sunlight are much less likely to have flea populations. If you have debris accumulating in your yard, it could be harboring fleas.

Piles of branches and leaves are ideal habitats for newly hatched flea larvae. Similarly, areas with lots of vegetation can be a breeding ground for fleas.

Fleas indoors will accumulate in the places your pet spends the most time. The same is true of your yard. Eggs laid on your pet will drop off, hatch and develop in areas your pet frequents.

flea eggs in carpet
Flea eggs between carpet fibers

If your pet has outdoor bedding or shelters (e.g. a kennel or dog house), they are likely infested with fleas at earlier stages of development.

If you have wild animals frequenting your yard, the places they spend time or nest can also be a hotspot for flea infestations. Your pet is likely to repeatedly investigate where the wild animal (e.g. opossum or squirrel) goes, causing repeated re-infections.

On this note, you can locate potential flea infestations in the yard by careful observation of your pet. Once you let your cat or dog outside, watch where they go. If your dog likes to patrol the fence of your yard, there might be fleas accumulating there.

Similarly, check shady areas near plants or garden sheds where your pet likes to rest. If your outdoor cat keeps slipping out through cracks in the fence or has a favorite shrub to lie under, these may be flea hotspots.

If you are still not sure if there are fleas in your yard, there is an easy way to find out. Wear pure white athletic socks with long pants, tucking your pants into the socks. Make sure no skin is exposed.

Walk around your yard for a little while in the socks. Adult fleas could jump onto the socks in search of their next meal. They will then be visible on the white fabric when you examine the socks. Dispose of the socks carefully before re-entering your home.

How to Get Rid of Fleas in the Yard

As you tackle the yard, you also need to get rid of any fleas on your furry family members. There is a range of flea treatments available for pets of all species and ages.

Consult your veterinarian to find the optimal choice for your pet, particularly if your animal is very young, elderly or in poor health.

Keep in mind that certain flea medications can be extremely dangerous to your pet if misused. If you have a multi-pet household, you may have to separate your animals while applying sprays, powders, or other spot-on treatments.

For example, even if a flea medication is not toxic to your dog, it can be poisonous to your cat if mutual grooming occurs.

If you’d like to be extra-careful, ensure you choose tried and tested flea sprays that are appropriate for your specific pet, or even look into making your own, using safe and natural ingredients.

Unfortunately, there is no simple solution to kill off fleas immediately. You have to employ different strategies simultaneously for the best chance at success. While you are treating any pets and your yard, you must also treat your home.

Take care to thoroughly vacuum to get rid of flea eggs, pupae and larvae. Pay special attention to the areas your pet spends the most time in.

Your pets will need to stay out of the yard until all the fleas are gone. Keep cats indoors and walk dogs on a leash outside of the home. If you must take dogs through the yard to get out of the house, do so quickly, keeping them away from the shade and shrubs.

You have a few options when it comes to killing fleas in your yard. I have reviewed three commonly used options to get rid of fleas outdoors. These include nematodes, diatomaceous earth, and chemical insecticides.

You will get to know how each works to kill fleas, and how effective they are.


Nematodes are a type of minute, unsegmented worm. There are various different sorts of nematodes, classified according to what they eat. Some species are the bane of agriculturists such as farmers, because they feed off plants.

Beneficial Nematodes
Beneficial Nematode

Others are similar to fleas, in that they are animal parasites. Insecticidal nematodes consume insects such as fleas, behaving as a live flea-killing agent.

Best of all, insecticidal nematodes will not damage any plants in your garden, and are harmless to humans and pets. These beneficial parasites need to feed off insects like fleas, in order to develop.

Beneficial Nematodes
Beneficial Nematodes

Juvenile nematodes enter the flea body through open cavities, such as the spiracles (respiratory tubes). Certain species of insecticidal nematodes can simply burrow directly through the flea’s body.

Once the juvenile nematode is inside the flea, it will release a special type of bacteria into the flea’s hemocoel. In insects, this is the cavity in which blood is stored.

The bacteria released by the nematode then attacks the flea’s blood and tissues, eventually ending in its death. The nematode can then feed off the flea, growing and developing. Eventually, it will produce more juvenile nematodes inside the dead flea.

Depending on the species, nematodes either wait for hosts to pass by (ambushing), or actively seek them out (cruising).

Diatomaceous Earth

The second choice you have is using diatomaceous earth, a unique type of insecticide. It is essentially the remains of fossilized diatoms, which are a species of algae.

Diatomaceous earth works to kill fleas by degrading their tough exoskeletons. Without this protective outer layer, the exposed flea will dehydrate and eventually die. It is just as effective on flea larvae as it is on adult fleas.

As with insecticidal nematodes, you don’t have to be concerned about killing off your plants along with the fleas. The skeletons of diatoms are mostly made up of silica, an element that is abundant in soils.

Diatomaceous earth is a popular insecticide among gardeners because it is non-toxic to plants and capable of deterring and killing numerous garden pests.

You can apply diatomaceous earth liberally throughout your garden. To be effective, ensure that the powder settles on the ground, even in areas with a lot of foliage.

diatomaceous earth
diatomaceous earth

It does not degrade in sunlight, and is best used in dry environments. If there is a heavy rainfall, you will have to re-apply the diatomaceous earth powder throughout your yard.

Some products containing diatomaceous earth come in liquid forms or can be made wet. You can review what type is most suitable for your region and climate.

When using diatomaceous earth powder, do not allow any dust to get into your eyes, nose or mouth. Keep children and pets away from the yard during the application process, to avoid accidental inhalation.

Chemical Insecticides

Finally, there are many chemical insecticides on the market that are potent weapons against fleas. However, these compounds carry a higher risk of accidentally intoxicating your pets, children and even plants.

If you choose to use a chemical pesticide, follow product guidelines exactly as indicated. For example, pyriproxyfen targets only fleas in the earlier stages of development. It stops fleas from multiplying by preventing larvae from growing into adults.

Although this pesticide is classed as being minimally toxic to adults and pets, it can be dangerous to children.

Permethrin is another frequently used insecticide in products against fleas, both on your pet and in the environment. It is a type of neurotoxin, meaning it attacks the nervous system of insects that come into contact with it.

This poison can be dangerous to pets, particularly cats. Keep in mind that it does not evaporate very easily and if mixed with water can remain on the surface of plants for up to three weeks.

Boric acid is another potent insecticide often used on fleas in the environment, both indoors and outdoors. Boric acid kills fleas that consume it by attacking their nervous systems. This option might not be appropriate for plant lovers, as an excess of boric acid can harm plants.

In combination with regular preventative insecticide treatments, keeping your yard neat is essential for flea prevention. Mow your grass regularly to keep it short, and ensure your flora and fauna is under control.

You don’t want to give fleas any opportunities to settle in. In some cases, you can prevent a repeat infestation by learning from your mistakes.

If the cause of your infestation was due to an opportunistic raccoon nesting underneath your deck, seal it off after it has been treated. If fleas were breeding in a pile of old gardening waste, do not allow refuse to accumulate again.

Remember that flea larvae do not do well in sunlight – get rid of extra debris or hanging vegetation that offer ideal nesting habitats for fleas.


Now that you know how to kill fleas in your yard, you can choose the strategy that best suits you. If you want to combine multiple techniques, check that the products you are using are compatible beforehand.

Some ingredients (particularly the chemical ones) can be dangerous if mixed together.

If you feel uncomfortable using pesticides on your own, you always have the option of contacting a professional pest control expert.

If you have fleas in your yard, do not ignore it. Infestations can spread not only into your home, but into the yards and homes of your neighbors.