How to Kill Grubs in Your Lawn
During the late summer and early fall, you may begin to notice lawns turning an unattractive shade of brown in certain unsightly, dying patches. The likely explanation is the grass is being destroyed by hungry, thriving grub worms living below the surface of the lawn. If this has happened in your lawn, there is good news. These pests can be controlled, and your lawn can be restored back to its healthy state by getting rid of grub worms.
Better yet, because of a growing preference for natural gardening solutions, there are now some easy and natural ways to kill lawn grubs and stop them from reappearing next year. This means you’ll be able to get back to enjoying your yard year-round without concern of nasty grubs eating away at it.
How Grubs Affect Your Lawn
Grubs are the larvae of many kinds of beetles, such as Japanese beetles or June bugs. Grubs can be found within your lawn during the late summer months after the beetles have laid their eggs around July. Female beetles lay their eggs about one or two inches deep in the soil. They will spend two to three weeks laying eggs and will each produce as many as 60 eggs in this time. Once the eggs hatch between the two-to-four week mark, these grub worms begin looking for food to fuel their growth.
The lawn grubs you’ll likely find are small, white, worm-like pests that live in the soil and feast on organic matter in the lawn. They will eat anything within the soil that’s in their path, including the roots of grass. By devouring the grass roots, they begin to kill off patches of your lawn, leaving it brown in certain areas. Grubs will continue to expand their destruction as they move under the lawn’s surface.
When severe destruction occurs from grubs in the lawn, it’s a result of the lawn’s health not being adequate enough to outpace the grubs feeding on it. In other words, a healthy lawn will grow faster than the grubs can eat it.
If your grass is unhealthy, you’ll want to kill these white grubs in the lawn immediately after finding them. Then take appropriate measures the restore your lawn’s health so it can withstand pests in the future.
The fewer mature female beetles you have in your yard, the less chance you will have of facing a grub problem later in the summer.
Signs You Have Lawn Grubs
There are certain signs to watch for to know if you’re faced with a grub problem. First of all, you may have noticed other wildlife being attracted to your lawn. This wildlife activity in your yard likely indicates you have a grub worm problem. Animals, such as raccoons, skunks and birds, enjoy grubs as a main part of their diet. If you’re serving up an assortment of tasty lawn grubs, then these creatures are going to get digging — which can also cause damage to your grass.
Secondly, you will notice dying patches of grass in your yard that are easy to pull up by hand. This is a clear indicator the roots of the grass have been destroyed as these patches are no longer thriving in the soil. You may have previously attributed dry, dying patches of grass to under-watering or environmental conditions. However, it is likely a grub problem, which is very common in North America.
Your natural inclination when you notice lawn damage caused by grubs might be to rip up the patches of grass that are browning and replace them with new lawn turf. This is, however, not the correct or sustainable solution. You can instead simply treat this area of lawn with a pest control treatment and begin your lawn care regime again. Once the grubs have been killed by the pest control solution, this will promote root growth in the grass, and it will begin to heal and regrow.
To know just how badly your lawn has been impacted, it is recommended to dig up one square foot of lawn. You’ll be able to easily lift up the browning patch of grass as it will pull up much like a carpet. Dig through the exposed section of soil and look for the white grub worms. You’ll notice these pests will curl themselves into a “C” shape when disturbed.
As a rule of thumb, a healthy lawn is able to withstand up to five grubs per square foot. If you find more than five grubs in this patch of grass, then you have an infestation that requires a pest control treatment. By testing multiple areas of your lawn, you’ll have a better idea of just how extensive the problem is and what you’ll need to do to get rid of the grub worms. If you only find a few, then it may be as simple as hand picking them from the affected areas, and then applying fertilizer and doing a deep watering.
It is also recommended to water your lawn infrequently when you’re treating a grub infestation as many won’t survive in the dried out soil.
Using Integrated Pest Management
Integrated Pest Management (IPM) is a natural pest control solution and process that uses beneficial insects and other biological solutions. Gardeners often choose these forms of pest control due to their lower environmental impact. Beneficial bacteria and diseases are alternative solutions for killing off white grubs long-term and protecting your lawn from infestations for years to come.
How Natural Predators Kill Lawn Grubs
Biological predators, like birds, raccoons, moles and more, are an option when it comes to grub control for lawns. You can choose to leave your soil exposed to welcome animals to devour the pests. For example, you can use bird feeders to attract birds to your yard to feast on the grubs. But do keep in mind, animals will dig holes in your lawn, which can cause further damage to your yard.
Milky spore is a beneficial bacterium and natural predator of Japanese beetle grubs. It comes in white powder form and can be released on the affected area of the lawn when grubs are present. When applied, milky spore will release spores which will infect the grubs and continue to multiply. The spores will reside in the soil for up to 15 years, meaning they will continue their outbreak against future grub invasions. However, this solution may not result in the desired outcome immediately.
Milky spore should be used independently of other pest control solutions because it requires the actual grubs present in the soil to take effect. This treatment is also best done on overcast days or in the evening when the sun won’t absorb it.
Another natural grub treatment is the use of beneficial nematodes, which are tiny worms that live in the soil and pursue grubs and other pests as hosts while they release infectious bacteria. Once the nematodes find a grub to reside in, they will release bacteria that kills the host grub. Nematodes will not harm plants, animals or humans, but they will attack pests and insects through built-in homing capabilities.
Nematodes can be applied in a liquid form. Like milky spore, nematode pest control treatments should not be applied in direct sunlight. Heavy watering is required immediately before and after applying the liquid nematode treatment.
Neem oil is naturally derived from the seeds of a tree found in India called the neem tree. Neem oil is used as a pest control solution for killing lawn grubs.
How to Kill Lawn Grubs on an Organic Lawn
As gardeners become increasingly concerned about using traditional chemical-based pesticides, alternative pest control solutions are growing in popularity. This is largely due to increasing education and awareness about the harmful impact of chemical pesticides. Many chemical-based pesticides will only get rid of lawn grubs initially, which often leads to the pests returning time and again as they will develop a resistance to the chemicals.
You may have tried do-it-yourself grub-killing solutions to ensure a chemical-free method of pest control. Some DIY solutions call for a combination of household products like mouthwash, lemon juice, liquid dish soap and water to create a spray that can be applied all over your yard. However, this homemade solution only acts as a deterrent for grubs and is not an effective or immediate way to kill them.
To truly eliminate your pest problem, you will need to apply a treatment that eliminates the grubs completely, which gives you the space to be able to restore your lawn’s health. Better yet, a treatment that can be applied to grubs at any stage of their life cycle will be a better solution for year-round pest control.
How to Kill Grub Worms If They’re Already Present
You will want to fertilize your lawn to keep it thick and healthy, and also be sure you’re mowing your grass down to a minimum of two inches in height — beetles prefer to lay their eggs in thin, sparse grass. It will be necessary to implement an infrequent watering schedule, too. When you do water your lawn, though, make sure to water it deeply to promote deeper and stronger growth of grass roots.
Grub Control for Lawns
Left unchecked, white grubs in your lawn will continue their destructive course and will eventually sever the roots of the grass so badly, it will be unable to regrow. Having your yard re-turfed is expensive and time consuming. Protect your lawn by using OMRI Listed® and compliant Safer® Brand products for a healthy and organic lawn.