How To Apply Beneficial Nematodes To Yard (Easy Fix)

Nematodes are often referred to as “good” or “friendly” because they eat other bugs. You can use them in gardens, lawns and potted plants to get rid of slugs, cutworms, grubs and a host of other pests. 

These tiny organisms can be applied directly to your soil or added to water used on outdoor plants. 

Beneficial nematodes live underground and feed on various types of insects including white grubs, Japanese beetle larvae, Colorado potato beetle larvae and more!

How to apply Beneficial Nematodes in the Garden by ARBICO
Key Takeaways from Tips to Improve Your Yard
Incorporating a French drain is a simple solution for standing water in your yard.
Improving yard drainage helps prevent costly maintenance issues such as water damage to properties or homes.
Absorbing standing water allows your yard to look clean and healthy without any waterlogging.
Adding shade can make your yard a comfortable place to spend time without worrying about sunburns.
Creating a private space in your yard can be done by using plants and fences.
Beneficial nematodes are tiny organisms that can control various insect pests.
They are not harmful to humans and do not affect beneficial insects such as bees and ladybugs.
They work best during optimal times of the year, such as spring and fall, and are most effective against certain pests.
It takes several days to weeks for nematodes to work depending on the severity of the infestation.

Use Them Indoors

Most beneficial nematodes are safe for humans and pets. They can be used indoors to control pests in the home, but not on areas where food is prepared or eaten. 

Nematodes won’t harm people or animals, so you don’t have to worry about them contaminating your food supply. 

The best way to apply them is by using a hose sprayer or watering can if you want to treat an entire yard or garden area.

If you’re using nematodes indoors, apply them directly into cracks and crevices where insects like cockroaches tend to hide out during the day such as underneath baseboards, behind pipes and outlets, under sinks and refrigerators 

(use caution not to get any water into electrical outlets), around door frames etc., since these places provide plenty of hiding places for these unwanted pests!

If you’re dealing with standing water in your yard, installing a French drain can be a simple and effective solution. This will not only prevent water damage to your property but also helps in draining the water out of the yard quickly.

Apply To Garden Beds

There are several ways to apply beneficial nematodes to your garden bed, including using a hose-end sprayer and a watering can.

Apply 1/2-1 gallon of water per 1000 sq. ft., which is the equivalent of about one 1-gallon bucket with a shovelful of soil in it, around plants and trees. 

Use less if you’re only treating small areas or when watering with a hose end sprayer (you don’t want to overwater). 

Depending on how much rain comes after application, this may be all that’s needed for your plantings and trees. 

If more rain is expected within five days of application and especially if it’s been very dry then apply again at week 3 or 4 for perennial gardens or shrubs that need regular irrigation during their growing season (eastern red cedar, mountain ash).

Apply To Sopping Lawns

This is the easiest way to apply nematodes. It’s best to use sprinklers or hoses to water your lawn before applying them. This makes sure that the soil is moist and gives them a good chance of survival. 

The next day, water again but do not over-water. If you don’t want to spend time watering with a watering can, you can also use a spray bottle filled with water and spray on top of the soil where you apply your beneficial nematodes.

Nematode applications are most successful when applied when there will be at least 24 hours without rainfall or irrigation after application. 

When this happens in summer months (June through August), this means waiting until nighttime has passed before applying nematodes so that they aren’t washed away by morning rains!

Poor yard drainage can cause a wide range of problems, not only with the landscaping and property but also within your home. By improving your yard drainage, you can avoid costly maintenance issues such as draining water from the basement and damaged foundations.

Use Them In The Soil

Beneficial nematodes are tiny worms that live in the soil. They are a natural way to control pests such as grubs, root maggots, thrips and caterpillars. 

They feed on other insects and larvae in the soil. Beneficial nematodes can be applied to the soil, leaves or roots of plants.

If you want to apply beneficial nematodes directly into the ground or lawn area where they will work their magic, you can use either a hose-end sprayer or an injector system like SNS (Seeking NemaSystem). 

You can also purchase them in liquid form and then mix them with water so that they’re easier to apply evenly throughout your garden space; just make sure you follow instructions carefully when mixing these solutions because improper ratios could kill your plants!

Use Them In Potted Plants

While beneficial nematodes should be applied to the soil in your garden, they can also be used on potted plants. 

This is particularly useful for overwatered or neglected plants that have been infested with pests or diseases. 

Additionally, if you know a friend or family member who has a problem with pests in their yard, you can give them some of your nematodes so that they can use them on their own plants. 

To use beneficial nematodes on potted plants, simply follow the same application process as outlined above:

  • Water thoroughly 2 days before applying nematodes
  • Apply desired amount of nematodes per square foot of potting soil (e.g., 1/4 tsp per 4 inches deep pot)
  • Water thoroughly again after application

When it rains, the standing water in your yard can quickly lead to mud formation all over on the surface. However, with simple techniques to absorb standing water, you can quickly prevent mud formation and help your yard look clean and healthy without any waterlogging.

Use Them On Seedlings

If you’re planting seedlings, apply beneficial nematodes with a sprayer at the time of planting. This ensures that the nematodes get right to work in helping your seedling establish itself. 

If you’re going to be using them on a bare-root plant, make sure to treat the soil surrounding it as well by sprinkling it with a handful of beneficial nematode pellets. 

This will ensure that they get established quickly and help keep pests from returning later on down the line.

Treat Pet Bedding With Nematodes

  • The application of beneficial nematodes to pet bedding has many benefits, including:
  • reducing the population of flies and other pests that pollinate your dog’s waste into festering piles of maggots;
  • preventing your dog from ingesting harmful bacteria from its own feces;
  • keeping flea larvae from growing on your lawn.

You can easily treat any lawn or area where pets are allowed to dig in their waste or play with a simple application of beneficial nematode soil drench. 

Nematodes will enter a host’s body through various openings mouths, noses, eyes and kill any parasites inside them within 48 hours after being ingested by the host animal (or human). This process is completely natural and does not harm animals in any way!

Creating shady spots in your yard can be an appealing way to spend quality time outdoors, but overexposure to the sun can be harmful too. With easy-to-implement ways to add shade to your backyard, you can enjoy the fresh air without worrying about getting sunburnt.

Apply On Winter Annual Plants In Fall

You should apply nematodes in the fall to control winter annual weeds such as crabgrass and other broadleaf weeds. 

The nematodes are winter active, so applying them in the fall will ensure they’re active when these pests emerge from the soil.

Apply On Spring Annual Plants In Early Spring

Nematode applications are best made in early spring, when annual plants are about three to four inches tall. Apply the beneficial nematodes when soil is warm and moist, but not muddy or flooded.

When temperatures are above 50 degrees F, apply the beneficial nematodes immediately after rain has stopped for at least two days. If it rains within 48 hours of application, re-treat your lawn or garden with dry granulars as soon as possible.

When it comes to backyard privacy, there are many ways to achieve it without spending too much of your resources. To get the job done right, check out our expert advice on adding privacy to your backyard which includes smart tips such as using plants and fences to create a cozy and secluded space in your own yard.

Use For A Spring Lawn Treatment

It’s also important to know that nematodes are not limited to the soil. They can be applied to grass and other plants as well. 

Nematodes are beneficial because they only attack pests, so they don’t harm beneficial insects like bees or butterflies.

You should use nematodes when you have a specific pest problem in your yard, such as grubs or fleas. It’s best to apply them in early spring or fall, before those pests become active again for the season.

If you’re looking for a way to naturally control the following:

  • grubs (commonly found in lawns)
  • mole crickets (these look like mini-moles)
  • ticks (some people have an allergy)
  • chiggers (tiny red bugs that burrow under your skin) then this is an ideal solution!

Best Time to Apply Beneficial Nematodes for A Spring Lawn Treatment

MonthsLawn ConditionTreatment
March – AprilHealthy LawnApply Beneficial Nematodes
May – JuneStruggling LawnApply Beneficial Nematodes + Grass Seeds
JulyDormant LawnWait until Fall for Treatment

Note: Applying beneficial nematodes during spring can aid in improving the lawn’s overall health and managing pests like grubs, among others. If your lawn is damaged or struggling, you can combine applying nematodes with sowing grass seeds in May and June.

The table provides an overview of the recommended months for applying beneficial nematodes to your lawn as well as the appropriate treatments based on your lawn’s condition. You should note that nematodes aren’t limited to soil and can help control pests on plant leaves as well. By following this table, you can have a healthier lawn in no time.

Apply On Summer Annual Plants In Mid-Spring Or Early Summer

You can apply nematodes to your yard in the early spring or late fall. The best time to apply is when the soil temperature is between 50 and 60 degrees Fahrenheit, but you can also apply them when the temperature is above 40 degrees Fahrenheit.

Nematodes have a high mortality rate at temperatures below 50 degrees Fahrenheit and above 80 degrees Fahrenheit. 

Nematodes are most sensitive to heat during their first week of life, so you should keep this in mind when deciding during which times of year you want to use nematodes on your plants.

The humidity level should also be between 60 and 85 percent for optimal results from using beneficial nematodes in your yard or garden.

Use For A Summer Lawn Treatment

You can also apply nematodes to your yard in the summer. This is a great option for areas that have had trouble with grubs or other pests, but you don’t want to use insecticides. 

Nematodes will help control many different kinds of lawn pests without harming the environment or your pets.

Apply beneficial nematodes in late summer or early fall before the ground freezes over for the winter. 

That gives them plenty of time to go through their life cycle and reproduce before freezing temperatures come along and kill them off.

Use For A Fall Lawn Treatment

Beneficial nematodes are not effective in winter, so you can apply them to your lawn in late summer or early fall. Beneficial nematodes will help control grubs and other insects that feed on your lawn, making it a healthier place for the grass to grow. 

Nematodes are not harmful to humans or pets, but they do have a limited shelf life and must be stored in the refrigerator until application.

If you have treated your lawn with pesticides this season (or ever), we recommend waiting at least 30 days after treatment before applying beneficial nematodes to ensure that any insecticides have time to work their way out of the soil.

Best Time to Apply Beneficial Nematodes for A Fall Lawn Treatment

MonthsLawn ConditionLawn Treatment
August – SeptemberHealthy LawnApply Beneficial Nematodes
OctoberHealthy-Weakened LawnApply Beneficial Nematodes + Fertilizer
NovemberDormant LawnFertilize Lawn Only

Apply On Fall Annual Plants In Late Summer Or Early Fall

Beneficial nematodes are available in many different forms. They can be applied to soil, lawns and potted plants both indoors and outdoors. 

Beneficial nematodes are safe for humans, pets and wildlife. Beneficial nematodes are a good alternative to pesticides.


If you’re still confused about when to apply nematodes, remember that these products are only effective if the soil temperature is over 50 degrees Fahrenheit. 

If it’s too cold out, don’t worry! You can always wait until warmer weather before tackling this project.

Further reading

Check out the Lawn Love Blog for insights on beneficial nematodes for pest control.

Read up on nematodes at Heeman Garden Center’s guide on nematodes.

Get more information on beneficial nematodes, including FAQs, at Arbico Organics.


What are beneficial nematodes, and how do I apply them to my yard?

Beneficial nematodes are tiny, worm-like organisms that feed on and control a variety of insect pests. They are available as live, soil-dwelling organisms that you can apply to your yard using a variety of methods, such as spray bottles or soil injectors. You can learn more about beneficial nematodes by checking out Arbico Organics’ FAQ section.

Are beneficial nematodes harmful to humans or plants?

No, beneficial nematodes are not harmful to humans or plants since they only attack insect pests in the soil. They do not affect other beneficial organisms such as bees, butterflies, or ladybugs.

Can beneficial nematodes control all kinds of pests?

Beneficial nematodes are highly effective against a variety of insect pests, including fleas, grubs, and Japanese beetles. However, they are not suitable for all kinds of pests. Some pests such as aphids, whiteflies, and spider mites live above the soil line, and beneficial nematodes can’t control them.

What is the optimal time to apply beneficial nematodes?

The optimal time to apply nematodes depends on the type of pest you’re trying to control and the climate you’re in. In general, the best time to apply nematodes to your yard is during the spring and fall when soil temperature and moisture conditions are optimal for nematodes to thrive.

How long does it take for nematodes to work?

Beneficial nematodes can take a few days to several weeks to establish and multiply in your yard, and the amount of time it takes for them to work depends on the severity of the pest infestation. In general, you should expect to see a reduction in pest numbers within a few days to a few weeks, and complete control of the pest problem usually takes three to six weeks.