If you’re dealing with lawn grubs then chances are you’re more than a little frustrated. These destructive pests can tear apart your lawn before you even realize you have a problem, and once you do, you typically have to wait even longer to address the issue.
But when to apply grub control, and when can you expect to see results? We’ll answer both those questions before diving into everything else you need to know about grub control here.
What Are Grubs?
Before you start treating your lawn for grubs, it’s crucial that you understand exactly what a grub is. The last thing you want to do is to spend a ton of money on a grub prevention product, only to realize that you don’t have any grubs in your lawn!
Because let’s be clear about one thing, while Timon and Pumbaa from the Lion King might use the term grubs to define all the various beetles and insects they eat, to the rest of us grubs refer to a specific type of beetle or insect in your yard.
More specifically, grubs are the larval stage of the Scarab Beetle. Many people often refer to them as “White Grubs,” and these beetles have many different varieties, including Japanese Beetles, June Bugs, and European Chafers.
It’s important to note the distinction here, because if you’re having problems with different kinds of bugs in your lawn, grub control might not help. Moreover, just because you have a lot of different bugs in your lawn, that might not even be a problem depending on the type of bugs they are!
Grubs live underground until they’re adults, but it’s during the larval stage that they’re the most destructive to your lawn. They’ll eat at the roots of the grass, and this will kill your lawn as they feast.
Making matters worse is the fact that they eat the most during the fall, which means once they kill all your grass, you won’t even have any time to repair your lawn until the spring.
When To Apply Grub Control
If you have grubs, you need to do everything you can to get them under control. And like with many pests, if you can kill the grubs before they start munching on your lawn, it’s far easier. But to do this, you need to have a basic understanding of the grub life cycle.
Mature grubs, now beetles, emerge in the early summer to feed and mate. By mid to late summer, they’re laying eggs in your lawn, and those eggs hatch in just a few weeks. Those grubs start to much on your lawn straight away, but the feeding frenzy really kicks off in the fall.
That’s why it’s best to apply grub control in either the early or mid-summer. You want to apply a product before any grubs’ hatch, but you don’t necessarily have to wait until the beetles lay their eggs.
Preventative grub control products will kill the eggs as soon as they arrive, and that’s the best way to take control of your grub problem!
Can You Apply Grub Control Too Early?
While you want to apply grub control early, there’s definitely a thing as too early. Most grub control products will work for about four months, so if you’re applying it before that, you won’t see the results you’re looking for.
Also, keep in mind that grubs don’t just lay their eggs for a week or two. They lay eggs for about one to two months, which means the earliest you can apply grub control is two months before they start laying eggs.
While early applications will yield the best results, you can definitely apply grub control too early and not get the results you’re looking for.
What To Do After Applying Grub Control
Unlike with weed control products, after you apply grub control, your job isn’t done yet. Directly after applying grub control, you need to water your lawn thoroughly.
You need to do this because grubs live underground, so applying grub control to the surface won’t do a thing. By watering the lawn, you allow the grub control to soak into the soil where it can be effective against grubs.
For the best possible results, you need to do this right away, even if the grubs aren’t underground already.
How Often Should You Apply Grub Control?
How often you should apply grub control really depends on the area you live. You shouldn’t need to apply grub control more than once a year if you apply it at the right time. However, if you need to apply grub control every year depends on how prevalent grubs are in your area.
If you didn’t see any grubs the year before, then chances are you don’t need grub control this year. However, some areas simply get hit by grubs year after year. If you live in one of these areas, you’ll need to apply grub control every year to keep things under control.
Keep an eye on your lawn year after year, and apply grub control as needed. If you notice an uptick in grubs on years that you don’t apply grub control, it’s probably a good idea to add it as a regular part of your yearly routine.
Acceptable Seasons for Grub Control
While early summer is the ideal time to apply grub control, what happens if you miss your window or if you want to get an early head start on things?
The truth is that grub control will have some positive results in both the summer and the fall, but during early spring and winter, it’s just about useless.
That’s because during the winter, grubs dig down further, and the grub control you apply will never reach them. Meanwhile, if you apply grub control in early spring, they’re only coming up to get out of the ground, and they won’t go back in to lay their eggs anytime soon.
You’re better off waiting just a few more months to apply grub control at the appropriate time, that way you can prevent grubs from coming back next year!
Also, while you can apply grub control in the fall, it’s far less effective than if you apply it earlier in the year. It’s better than nothing, but chances are you’ll still have some grub problems until you reapply the grub control next summer.
Signs of Grub Problems
Because grubs typically live underground, it can be a bit challenging to figure out if you have any in your lawn, but challenging doesn’t mean impossible. Below we’ve highlighted a few signs that you might have a grub infestation on your hands.
Dead Patches of Grass in the Spring
While grubs start tearing your lawn apart in the late summer and fall, there’s a good chance you won’t realize you have a problem until the following spring. That’s when the rest of your lawn will start to turn green and luscious, but you’ll start to notice you have dead patches that won’t come back.
These are areas where grubs have torn up the roots to the point that the grass won’t grow back. If you have a grub infestation in your yard, there’s a good chance that you’ll have more than just one dead patch.
Pests Digging Up Your Yard
Just because you can’t tell that there are grubs underneath your yard just by looking at it, doesn’t mean that various wildlife can’t tell either.
Raccoons, skunks, armadillos, and some birds all feast on grubs, and they all have their own ways to find them. While you might think that these pests would act as a natural grub control method, the problem is that they can’t get enough of them, and they’ll tear up your lawn looking for more.
So, not only will you have dead patches everywhere from the grubs, but you’ll also have holes and other kinds of lawn damage from the animals trying to eat the grubs.
But they at least will give you a good idea that you have a problem and what that problem is!
Easy To Pull Patches of Lawn Up
If you have dead patches of grass in the spring, you should head over to investigate what’s going on. If you have a sodded lawn, you’ll notice that it’s easy to pull up entire patches of lawn, and that’s a surefire sign that something has eaten all the roots.
This is typical of grubs, so there’s a good chance that your lawn has an underlying grub problem. There’s also a small, but possible, chance that you’ll spot some grubs when you pull these sections up.
If you’re noticing these sections in the fall, see if you can’t gently pull up adjacent sections without tearing apart your lawn. If you can, there’s a good chance you might be able to spot some grubs and give yourself a definitive diagnosis.
Lawn Feels Spongy
While every other symptom we’ve highlighted here comes into play only after you notice lawn damage, a spongy lawn is a rare symptom that you can notice before any damage occurs.
As grubs eat the roots of the grass, it can start to “sag” when you exert force on top of it. This will feel like it’s just rained even when it hasn’t. If you notice that you have spongy grass, you should investigate further because if you let it go and the problem is grubs, they’ll end up damaging your lawn.
If you do discover grubs at this point, go ahead and apply a grub control product, even though this isn’t the best time. Applying grub control in the fall is better than no grub control at all, but expect that you’ll still have some lawn damage and that you’ll need to apply next year during early summer.
How To Check for Grubs
Since grubs live underground, there’s really only one good way to check for them – start digging. We completely understand that you don’t want to tear up your entire lawn though, and that’s why we recommend only checking a single square foot of your yard.
If you think one area is the problem, simply dig up one square foot in that area and check for grubs. If it’s the fall, you should only have to dig up 1 to 3 inches to check. If you notice six or more grubs in that area then you likely have a problem and need to apply grub control.
However, if you notice a smaller amount then you have two options. First, you can ignore them, since a small number of grubs shouldn’t harm your yard.
But if you count a more borderline number like 3 to 5 grubs, you can always check a separate section of your lawn to see how many there are. If you’re noticing 4 to 5 grubs in both locations, you might still want to apply grub control just to be on the safe side.
If you notice less than 3 grubs in the first section you check then you should be good to go, but you can always check more than one area or still apply grub control if you want to play it safe.
Unlike weed killers, grub control does not negatively impact your grass, and if you water in the grub control, you don’t have to worry about it around pets or children. Additionally, you can check this video for breakthrough
Deciding When You Need Grub Control
Not all grubs are bad. In fact, if you only have a few grubs and they’re not damaging your yard, you don’t need to do anything about them! But if you’re starting to notice adverse effects from the grubs, you should take action to keep an infestation from ruining your lawn.
If you pull up a square foot of lawn and find six or more grubs, then you have too many, and you need to apply some grub control. If you don’t take action, then there’s a good chance your lawn will suffer as a result.
Tips for Selecting Grub Control
If you’ve found grubs in your lawn, you need to get the right product to kill them or keep them from coming back. We’re not going to highlight any individual product here, instead we’ll walk you through everything you need to know to get what you need.
If you’re trying to get grubs under control, the best thing you can do is prevent them from hatching in the first place! Not only does this prevent all lawn damage, but it’s also far more effective.
While some of the best products that kill grubs have a 50 percent effective rate, prevention products can have up to a 100 percent effective rate!
Active ingredients that you should look for in any grub prevention product include imidacloprid, thiamethoxam, or clothianidin. But keep in mind that prevention products only work in the early to mid-summer. That’s because they don’t actually kill grubs, they just kill eggs, so you don’t get grubs in the first place!
However, if the grubs have already hatched then these active ingredients won’t do a thing. And if you apply them in the spring, then there are no eggs yet to prevent them from hatching, and by the time they do come, the effects have already worn off.
Products that Kill Grubs
If it’s already fall and grubs are taking over your lawn, it’s too late for preventative products. Instead, opt for an insecticide that contains either carbaryl or trichlorfon. Products with either of these chemicals will kill grubs on the spot, but neither last long.
This means that if you don’t get the grubs the first time, the product will dissipate, and the grubs will keep on living their lives.
These products likely won’t kill all the grubs in your lawn, but they will significantly reduce their numbers. Expect that grub-killing products will kill anywhere from 20 to 60 percent of the grubs in your lawn.
If it’s already winter then there’s no reason to apply any of these insecticides. The grubs can already be eight to twelve inches below the surface at this point, and the insecticides will never get far enough down to kill them.
Also, while grub prevention products are generally safe around kids and pets, that’s not the case with grub-killing products.
These chemicals are much harsher, and they can have adverse effects on kids and pets. Because of this, try to have them avoid treated areas for at least 24 to 48 hours to be safe.
Finally, you’ll still need to water the area right after application to get the insecticide down to where the grubs live. The grubs are still underground, so if the insecticide stays on the surface, it won’t do you any good!
Thoroughly water the area right after you apply the insecticide for best results.
Insecticides to Avoid
If a product doesn’t have any of the active ingredients we mentioned above, and only has chemicals like lambda-cyhalothrin, deltamethrin, or cyfluthrin, there’s no reason to apply them for grub control.
These products stay on the surface of your lawn and never reach the grubs, so they won’t help with getting them under control!
But many of the insecticides will have some of these active ingredients and active ingredients of either carbaryl or trichlorfon. The higher the percentage of the latter two ingredients the better, as they’re the insecticides that will work against grubs.
With that in mind, just because a product contains one of the previous insecticides doesn’t mean they won’t work against grubs. It’s just important to ensure that one of the other active ingredients will work against grubs
If it’s your first time dealing with grubs, you’re bound to have a few questions. We want to help you get your grub problem under control right away, and that’s why we addressed four of the most frequently asked questions here.
What Month Should You Apply Grub Control?
While it really depends on your region, you should be safe applying grub control in June, no matter where you live. If grubs have already started laying eggs at this point, they still haven’t had time to hatch, but in most regions, the egg-laying hasn’t even started yet.
We know June can be hot, and the last thing you want to do is to head out and apply grub control, but that’s when you’ll get the best results.
Will Grass Grow Back After Grub Damage?
Grass can absolutely grow back after grub damage, but for the best results, we recommend laying down some grass seeds. This will speed up the process, reduce the likelihood of weeds, and guarantee that you have the same type of grass throughout your lawn.
But as long as you take care of the underlying grub problem, there’s no reason your grass won’t grow back.
Do Grubs Come Back Every Year?
Grubs live in cycles, and as such, they typically will come back year after year. A significant exception to this is June Bugs, they live in a 3-year cycle.
However, it all depends on your particular area too. If your lawn is the only area where the grubs have been laying eggs, once you take care of the infestation, you may not have any problems next year.
At What Temperature Do Grubs Stop Feeding?
While no set temperature will send grubs underground, they typically stop feeding and dig a bit further when the soil temperature drops below 50 degrees Fahrenheit. This is a big difference from the ambient temperature, as the soil temperature typically takes a little longer to change.
White grubs can be one of the most annoying and destructive lawn pests, if you stay committed and use the right products, there’s no reason you can’t get them under control in just one season.
Just keep in mind that you have a relatively small window for the best results and that you might have to reapply every year to keep your lawn healthy and grub-free. So, take a deep breath and get ready because this is the year you can finally have a grub-free lawn!