Has your lawn become overrun with unwanted insects? If your lawn is being damaged by pests then it’s time to do something about it.
Unfortunately, a big infestation won’t go away on its own.
Lawn insect killer granules work quickly and efficiently to rid your lawn of insects, so you can restore it back to full health.
We’ve rounded up and reviewed the best lawn insect killer granules on the market for you to pick from.
All these options are effective, fast and offer good value for money. We’ve included both organic and inorganic pest control methods, but we recommend going for the natural options if you can.
The products protect against a wide range of insects including ants, chinch bugs, mole crickets, fleas, ticks and grubs.
EcoSMART insect granules are a non-toxic, organic insecticide that work on over 100 different types of insects. The brand’s mission is to create the worlds safest and most effective pesticides, using minimum risk ingredients.
Their formulas are based on over 15 years of scientific research and emulate a plants natural defences against insects. Clove and Thyme essential oils are the active ingredients and work by attacking octopamine neuro-receptors in insects. This affects their movement and metabolism, killing the bugs fast without leaving any harmful residues. Only insects have these receptors, which is why the product doesn’t harm other animals. The only other two ingredients are wintergreen oil and peanut shells.
When you use the granules as directed, they have no adverse effect on children, pets or the environment, including water systems.
The botanical mixture also has repellant properties to help keep insects from coming back to the treated areas. EcoSMART recommends you reapply every 4-6 weeks, or after particularly heavy rain. The granules come in a 10 lb bag that will cover 5,000 square feet.
The oils have quite a strong smell which can be overwhelming if you’re sensitive to fragrance. But you might also find it quite pleasant! Other natural insect killers like Johnathon Greens organic insect killer and Eco logic lawn insect killer use different plants oils such as rosemary or corn mint, so have different scents.
Active ingredients: 2% Clove Oil, 0.06% Thyme Oil
This two in one product kills lawn insects and strengthens your lawn with one application It’s also guaranteed not to burn your lawn. The product is designed to be applied in summer from June to August.
It improves your lawns ability to absorb moisture and nutrients, meaning it’s better able to cope with the heat of summer and any potential droughts. At the same time, it protects against a range of insects including ants, chiggers, chinch bugs, fleas, grasshoppers, mole crickets, sod webworms (lawn moth larvae), ticks and weevils.
One thing it won’t kill is grubs. If you have a grub problem, then you’ll have to buy a separate grub control product. Scotts Turf also sells a very highly rated product called Grubex which claims to prevent any grub problems for up to four months. Or you can use the milky spores we recommend below.
You have the option to buy enough granules to cover 5,000 or 15,000 square feet. You can also purchase a bundle with a Scotts mini broadcast spreader to make the application process super easy.
Active ingredient: 0.086% Bifenthrin
Spectracide is a kill on contact insecticide that kills bugs above and below the ground. The granules boast season-long protection against one of the most common lawn incests, ants, as well as protecting against over 100 other different insects.
The brand lists grubs as a bug the granules will kill, and several users have had success using it to treat grubs. However, the only active ingredient is Gamma-Cyhalothrin which a study from Michigan State University concluded won’t kill the beetle larvae on its own.
Spectracide has a larger coverage area than most lawn insect killers covering up to 12,500 sq ft with a 10 lb bag. If you have a large lawn, then you can get the 35 lb bag which can cover an impressive 44,000 sq ft. You should apply the product whenever you notice lawn damage that could be indicative of insects. If you’re trying to treat grubs, Spectracide recommended you apply it between July and October for maximum effectiveness.
The product is safe for pets and people once it has been watered in and left to dry.
Active ingredient: 0.08% Gamma-Cyhalothrin
Ortho Home Defense insect killer for lawns uses Bifenthrin as the active ingredient to kill bugs within 24 hours. As well as killing the insects on contact it creates a barrier over your lawn to keep the insects away for three months.
The formula works best if you apply it proactively in the early spring or summer to catch infestations before they happen. Otherwise, use it as soon as you see any signs of insect damage. As with other chemical treatments, you’ll need to water the granules after you’ve applied them. Make sure to wait for granules to dry before letting your pets onto the lawn.
The granules come in three different sized bags ranging from 2.5 lbs to 20 lbs, so there’s something to suit all lawn sizes. The 2.5 lbs bag is very affordable and comes with a special shaker container which means you don’t need to purchase a separate spreader.
Active ingredient: 0.115% Bifenthrin
Milky spore is a disease spread by bacteria that’s extremely effective at killing grubs. It’s an organic, natural and non-toxic method of grub control.
These granules are harmless to all living things apart from grubs, including all aquatic life and other beneficial pollinating insects. Unfortunately, this does mean the granules won’t be effective against other pests like chinch bugs or ants.
You can spread the granules any time between early summer and fall as long as the soil temperature is above 65 degrees Fahrenheit. Below this temperature and the grubs will be too cold for the treatment to work. The colder your climate, the longer it will take for the granules to work.
When a grub ingests a spore, the spore multiplies rapidly within the grub, killing it in about a week. As the bug decomposes, millions of new spores are released into the soil, and the process starts again. Eventually, there’ll be so many milky spores in your soil that grubs won’t be able to survive. To see the full effect of the spores can take about 2-3 years but after that, your lawn will be free of grubs for up to 20 years! The brand guarantees a grub free lawn for up to 10 years.
A 20 lb bag can cover up to 7,000 square feet which is a smaller coverage than other granules offer, but we think this is more than made up for with the longevity of the product. They offer multipacks if you need more coverage.
Active ingredient: Paenibacillus popilliae bacterium
While not technically a granule, we’ve included this powder because it’s another good eco-friendly alternative to chemical pesticides. It’s made from a sedimentary rock which is abundant all over the world – according to the National Pesticide Centre the rock makes up around 26% of the Earth’s crust.
The organic powder works by absorbing lipids from the insects’ waxy exoskeletons, thus dehydrating and ultimately killing them. To apply it you just need to sprinkle a light dusting all over your lawn. If you’re wanting to make the application process as easy as possible, you can purchase a Diatomaceous Earth applicator along with the powder.
Because of the product’s dry nature, it’ll be washed away whenever your lawn comes into contact with water. This means the product will need to be reapplied regularly (unless you live in a very dry area). Also, the product doesn’t seep into the soil like other chemicals, so isn’t effective on bugs that live under the surface.
It’s not just pest control that you can use Diatomaceous Earth for, there’s a wide range of uses cases including pet care and cleaning.
Active ingredient: Diatomaceous earth
While this insect killer is very effective, it contains harmful ingredients that we wouldn’t recommend using on your lawn.
The BioAdvanced insect killer for lawns has a two-way formula that’s effective on both soil and surface insects. It claims to kill surface insects such as ants, fleas, mosquitoes and mole crickets within 24 hours. And will keep soil bugs like grubs and European crane fly larvae at bay for up to three months.
However, one of the active ingredients in this insect killer is imidacloprid. Imidacloprid is part of the neonicotinoid family and is effective at treating grubs. However, it’s also highly toxic to pollinators like bees and butterflies. The use of this chemical has been banned in Europe since 2018, and in January 2020 the EPA advised homeowners not to use it. They’re also currently proposing to ban the use of imidacloprid on residential lawns.
Bonide is another popular lawn insect killer that uses imidacloprid as an active ingredient, and therefore another product we’d avoid.
Lawn insect killers come in two different formats: solid granules and liquid sprays.
Using granules has several significant advantages over using a liquid product. Perhaps the biggest one is in terms of safety. With granules, there’s no prep involved, and you never have to handle the product. Liquids tend to come in a concentrated form that you need to mix with water before use. This creates a risk of spillage or getting the concentrate on your skin which can cause severe irritation.
Some liquid bottles come with hose attachments to make dilution easier, but users have complained these attachments are prone to leaks that can be dangerous for children and pets. If you use granules, then there’s no need to worry about this.
Another advantage of granules is that you can quickly see when you’ve used enough product. With liquids, it can be easy to use too much just because you can’t always remember where you’ve already sprayed. This makes granules more economical because they’re a lot harder to waste.
Before you apply any insect killer to your lawn, you should mow the grass. This will maximise the chances of the treatment coming into contact with small bugs that could otherwise use the tall grass as cover. Mowing will also help scare away beneficial insects like bees that you don’t want to kill.
Because granules come pre-prepared they’re very easy to use. If you’re only treating a small area, then the granules can be spread by hand, just make sure you wear gloves! For larger areas, it’s advisable to use a spreader.
You might already own one if you’ve ever overseeded your lawn, but if not they’re pretty cheap to buy.
We recommend this mini broadcast spreader from Scotts Turf. It’s made in the USA and comes with edgeguard technology to prevent any product accidentally ending up on your flower beds or driveways. It can hold up to 5,000 sq ft worth of insecticide.
Once you’ve evenly covered your lawn, most granules require you to water them straight away. The water helps the active ingredients to penetrate the soil and get to work killing any unwanted pests. You usually need to wait for the lawn to dry again before it’s safe to allow pets and people back into the yard.
When to use an insecticide can vary depending on the type of bug you’re trying to treat. Generally, the best time to apply them is in early summer. Although you might not have a serious bug infestation yet, the insect killer works preventatively to stop insects ever becoming a real issue. The next best time is as soon as you spot any kind of damage potentially caused by lawn pests.
In terms of weather, you should avoid applying most treatments in the midday sun or if heavy rain is forecast in the next 24-48 hours. Too much sun will evaporate the product before it’s had a chance to work its way into the soil. Too much rain can wash the product away before it’s had a chance to bed into the soil.
Lots of people will notice their grass wilting and assume it’s something to do with their lawn not getting enough water, or not having the right nutrients. It’s easy to assume this without ever suspecting bugs as the root cause. But whenever you spot any sort of problems with your lawn, it’s always best to check if you have an insect problem.
Bugs that live on the surface of your lawn are usually easy to spot, as long as you know to look for them.
Surface feeders like armyworms are easy to see
Some insects such as sod webworms are only active at night, so can be harder to see. However, sod webworms turn into moths which are easy to spot as they fly away when you mow the lawn.
Naturally, it’s impossible to see underground bugs. However, there are some telltale signs to look out for such as moles digging in your lawn looking for grubs to eat. You might find our article on how to fix a bumpy lawn useful if you have a mole problem! Another thing to look out for is unexplainable patches of dead grass.
Grubs hide under the surface and feed on roots
Insects that live below the surface tend to chew away at your grass’ roots for food, killing your lawn in the process.
If you’re not sure, you can always dig up a section of your soil and see how many bugs you find. As an example, if you find more than six grubs in a square foot, then you have a grub issue.
Most insect killers contain chemicals that are toxic to animals and humans if ingested. However, this is only true for the raw product. After you’ve watered your lawn and left it to dry, there’ll be very little residue left meaning it’s safe for your pets to roam around.
Natural options often contain essential oils which have much lower levels of toxicity but can still be irritating to smaller pets such as cats.
There are two types of insect killers, natural and synthetic.
Synthetic killers can either be contact killers or systematic killers.
Systematic killers like imidacloprid are taken up by plants and then kill any insects that eat the plants.
When insects eat the treated grass, they die shortly afterwards
Imidacloprid is part of the neonicotinoid family of pesticides and works by targeting the insects’ nervous system. Once the bug has ingested the chemical, they die extremely quickly. Systematic killers are very effective against grubs because they feed on plant roots.
Contact killers, on the other hand, kill insects as soon as they come into direct contact with them.
Insects die shortly after touching contact killers
Pyrethroids are the main family of contact killers that are used in residential insecticides. Bifenthrin, Cyfluthrin and Cyhalothrin are common examples. Like systemic killers, contact killers also work by disrupting the insects’ nervous system.
Natural insect killers work in different ways depending on what the active ingredient is. Typically, they use essential oils which block vital receptors that the insects need to survive.
Wherever possible we recommend using natural methods because they’re less harmful to us, the environment, and other animals. However, when your lawn is completely overrun and needs immediate attention, sometimes the only effective method is to use a chemical product.
Synthetic chemicals such as neonicotinoids and pyrethroids are toxic to aquatic life and can contaminate groundwaters. In low concentrations, chemical insect killers aren’t harmful to mammals or birds, but if you ingest them or breathe in too much then you may experience adverse effects.
On the other hand, natural products made from organic substances have no adverse effects on the environment including water systems. You can safely use most natural products around pets without any fear of irritation, as the active ingredients they use are only harmful to insects. The only downside is that they can take longer to work.
Most insect killers aren’t selective about the type of insects they kill. This is both good and bad at the same time. It’s good because you can get rid of several pests at once, but bad because you also kill beneficial insects such as bees.
Pest control can have a devastating impact on bee populations and local ecosystems if you don’t take the right precautions. As we mentioned earlier, if the chemicals find their way into water systems, they can also cause harm to aquatic creatures. Here are some of the ways you can minimise the effects your lawn insect killers have on the environment:
Bees are attracted to flowers in lawns. This can be dangerous if the garden has been treated with insect killer
There’s a lot to think about when picking a lawn insect killer granule.
Our top choice is the EcoSMART insect granules. They’re effective against a wide range of different pests and are made using natural ingredients that don’t cause harm to the surrounding environment.
Have you had success with any of the above products? Get in touch, we’d love to hear from you.