Milky Spore vs GrubEx

Milky Spore vs GrubEX (which is best for your lawn?)

Grubs are one of the most common and damaging lawn pests in the United States. They can quickly destroy a beautiful, well-maintained lawn, making it look unsightly and unhealthy. Today, I’m bringing you my Milky Spore vs GrubEx comparison, to help you choose the best option to get grubs out of your lawn. is reader supported. If you make a purchase after clicking a link, I may earn a commission at no additional cost to you.

Milky Spore and GrubEx are both very effective treatments for grub control.

Overall, milky spore provides a better long-term solution (as long as you continue to do the recommended applications). On the other hand, GrubEx is more effective in the short term and has guaranteed results for up to 4 months.

The severity of your grub problem will determine which of these treatments is best for your lawn.

If you have a severe infestation, GrubEx may be the better solution since it can provide quick results but won’t hold up in the long-term as well as milky spore.

Trust and Accuracy Information

This article was last updated on by Lawn Chick Owner Sarah Jameson
Article content reviewed for accuracy by Horticulturist Arthur Davidson, A.S. Cost analysis by Managing Editor Joe Hessert, M.F.A

Signs of a Grub Problem In Your Lawn

All throughout the US, grubs are a problem that homeowners and lawn maintenance companies face. Fortunately, there are some ways you can tell if you have a grub problem in your lawn.

Signs of a Grub Problem in a Lawn

Some of the most common signs of grubs include brown patches in the turf, wilting or yellowing grass, and easily pulled-up grass that is dead underneath. You may also notice an increase in birds and other animals digging in the turf, looking for food.

It’s important to remember that all healthy lawns will have some grubs – this is simply a part of the life cycle of beetles and other insects.

But if it’s at the point where you can easily find grubs on the surface or your lawn is suffering damage, then it’s definitely time to take action before the problem worsens.

If left untreated, grubs can cause considerable damage to your lawn and create a breeding ground for other destructive pests.

There are numerous organic and synthetic ways to control grubs, but the two most popular and effective treatments I’ve personally used are Milky Spore and GrubEx. Depending on the severity of your grub problem (and the type of beetle grubs you’re facing), you will want to choose which treatment is right for you.

What Are Milky Spore And GrubEx?

Let’s talk about the components of each treatment and how they work (because they work differently).

About Milky Spore

Milky Spore is a type of bacteria called Bacillus Popilliae. It works by killing grubs, specifically the larvae of Japanese beetles.

You spread the bacteria throughout your lawn, and it will work over the course of several years to establish itself and control grub populations. recommends 6 treatments – 3x annually for two years. After that, you can enjoy soil that will be largely grub-free for the next 20 years.

What Are Milky Spore And GrubEx

Lawns that have recurring problems with moles will often use Milky Spore as a solution as it removes the primary food source, and the moles are less likely to invade or remain in the lawn.

But a note about this product – if you live in an area where your grub population is not Japanese Beetles, it may not be effective. I was contacted by a reader from Florida who judiciously applied it but saw no noticeable difference in her yard’s grub population. She was understandably frustrated, but when I explained to her that Florida didn’t typically have Japanese Beetles, things began to make sense.

As with any pest-control or weed-control product, you won’t get results if your targeting is wrong.

About GrubEx

GrubEx is a granular insecticide that kills grubs on contact and provides protection for up to 4 months. It is most effective when applied in the spring or early summer, when grubs are most active and vulnerable.

GrubEx is produced by Scotts and is specifically designed to be applied with a Scotts spreader. Getting an even application is important with GrubEx, as uneven distribution can cause areas of your lawn to be over-treated or under-treated.

If you have a spreader that’s a different model, just measure your lawn size, and work backward from the bag’s recommended square footage coverage to dial in your application.

Both Products Work Well, but Work Differently

Depending on the intensity of the grub problem, you can use either of these products to achieve a grub-free lawn.

  • Milky Spore is ideal for long-term protection, while
  • GrubEX works best in the short term but may require more frequent reapplications if the grubs return.

My Advice, Based on Hands-On Experience with Both Products

  • If you live in an area with an active Japanese Beetle population, my recommendation would be to apply Milky Spore three times annually for two years, then enjoy two decades without having to think about grubs in your turf again.
  • However, if you have a grub problem and live in an area where Japanese Beetles are not present, or if you simply prefer to incorporate an annual insecticide application into your existing lawn fertilization schedule, GrubEx will be the better choice for you.
  • Finally, if you do not have a history of grub problems in your yard, don’t apply either product and just let mother nature do its thing.

Cost Comparison: Milky Spore vs GrubEx

Comparing the costs of Milky Spore and GrubEx comes down to a few factors, including the duration of the treatment, the size of your lawn, and how often you will need to reapply.

Cost Comparison Milky Spore vs. GrubEx

Other factors you may want to consider include how long you plan to live at your current address.

I’ve done the math, and over a 20-year period, applying Milky Spore 6 times in the first two years is 62.86% cheaper than annual applications of Grubex.

That said, Milky Spore doesn’t become the more cost-effective option until year 8, so if you aren’t concerned with long-term savings or plan to move in a few years, annual applications of GrubEx might be the better choice for your wallet. In year one, the single GrubEx application will be 73.07% cheaper than your 3 applications of Milky Spore.

Comparing How Much You’ll Pay The First Year

Lawn SizePrice of Milky Spore
(3 applications in year 1)
Price of GrubEx
(1 application in year 1)
2,500 square feet$52.92$14.25
5,000 square feet$105.84$28.50
10,000 square feet$211.67$56.99
In the first year, GrubEx is 73.07% cheaper

Comparing How Much You’ll Pay Over 20 Years

Lawn SizePrice of Milky Spore
(6 applications in 20 years)
Price of GrubEx
(20 applications in 20 years)
2,500 square feet$105.84$284.95
5,000 square feet$211.67$569.90
10,000 square feet$423.34$1,139.80
Over a 20-year period, Milky Spore is 62.86% cheaper

* Note * This pricing comparison is based on current pricing at the time of publication, and ~$0.0071/square foot for Milky Spore and ~$0.0057/square foot for GrubEx

For me, the 18 years of grub-free peace of mind with no additional maintenance (and the fact that Milky Spore is a natural product) both provide significant value. It’s what led me to choose Milky Spore for my property.

But lets dig in a little deeper.

The Best Long Term Option

Milky spore is a long-term solution that doesn’t require frequent re-application, making it cheaper in the long run. Establishing the milky spore bacteria is key in controlling grubs, and it can take up to 2 years in order to get a solid foundation of the bacteria in your lawn.

Each 20lb bag of milky spore can cover up to 7000 square feet, making it an effective choice for smaller lawns as you’ll get multiple applications out of one bag. The granular version of Milky Spore is easy to apply with a spreader, and it’s safe for kids and pets who may frequent your lawn.

The Best Option For The Short-term

GrubEx is a short-term solution and will require more frequent re-applications if you have an active grub problem. Using GrubEx will give you very fast results, and it can last up to 4 months, giving your lawn and garden a solid chance at recovery.

You can use a single 14.35lb bag on more than 5,000 square feet, which makes it a great choice for larger lawns. You activate GrubEx by watering it, so you’ll need an effective sprinkler system if you have a larger lawn and want the best results.

While it takes multiple applications of milky spore to get it established, once it is established, you won’t have to worry about grubs anymore. However, if your grub problem comes back 4 months after putting down GrubEx, you’ll have to use it again.

So, in many cases, you’ll end up spending more money in the long run if you go with GrubEx. However, if you have a severe grub problem and want to get rid of it right away, GrubEx is worth the cost.

With milky spore lasting up to 20 years after it’s established in the soil, you’re going to have a much better long-term solution to grubs and other pests that they attract. That’s why in the long run, milky spore tends to be more cost-effective than GrubEx.

Which Product Is Safer? Milky Spore vs. GrubEx

If you have kids or pets, product safety should be one of your top priorities. Both products are considered generally safe as long as you follow the instructions on the product packaging.

Which Product is Safer Milky Spore or GrubEx

That said, to my way of thinking Milky Spore is safer than GrubEx.

It’s a natural product and doesn’t contain any active chemicals that could be harmful to people or animals.

It’s also safe to use in ponds, streams, and other water sources as it’s completely non-toxic.

Some mild irritation can come from skin or eye contact with milky spore, but this is rare and you can easily avoid this problem by following the instructions for proper use. For extra protection, you can wear protective clothing, gloves, and face masks during application, and I recommend applying either product on a calm day without wind.

Unlike milky spore, GrubEx contains an active chemical. It’s called chlorantraniliprole, and it can be harmful if inhaled or ingested, so it’s important to take precautions when using this product.

While PPE is recommended for Milky Spore applications, you must take precautions when applying GrubEx. Wear protective clothing, goggles or safety glasses, rubber gloves, and a respirator.

After you’ve applied the GrubEx and watered it in, wait until it dries. After that, it should be safe to re-enter your yard according to the manufacturer.

Tips for Applying Milky Spore or GrubEx Effectively

In granular form, both products are quite easy to apply.

Are you going with milky spore? You’ll have to apply it periodically over a 2-year period for the bacteria to get established in the soil.

Tips for Applying Milky Spore or GrubEx Effectively

By contrast, you only have to apply GrubEx once to get rid of your grubs. However, this effect may only last 4 months.

That means that if the grubs come back, you’ll have to re-apply the GrubEx.

Now, let’s talking about how to spread the products. I recommend using a good fertilizer spreader so that you can consistent application all over your lawn.

Using a spreader will also help you stay within the recommended application rates and prevent over-application.

You can adjust a spreader so that you put down the right amount of product as per the manufacturer instructions. Make sure to check the product label for any specific instructions on how to apply it.

Are there any obstructions on your lawn? Remove them before you do application.

This is essential for making sure that you put down your chosen product evenly.

Make sure that you move over your lawn in a consistent pattern with your spreader. Take note of parts of your lawn that are difficult to reach and adjust the spreader accordingly.

It’s also important to ensure your lawn receives the appropriate amount of water to activate the product. Check the instructions on the product packaging to find out how much water to provide.

Lawn Chick Tip for Success

Whenever I apply granular products I start by accurately measuring my lawn’s size (you can use my free lawn size calculator here).

Demonstration of Measuring a Lawn Using's Lawn Size Calculator

Then, I calculate the correct amount of product based on the manufacturer’s recommended application rate and my lawn’s square footage.

Next, I half the material I’ll need. I walk the perimeter of my lawn with the spreader first, putting in a header strip so that as I make turns when applying the product the edges have good coverage too. I apply the balance of product in my spreader in a back-and-forth pattern (north to south).

Spreader Path

Finally, I had the reserved product to my spreader, and apply that in the opposite direction (east to west).

Spreader Path 2

This technique helps to ensure an even application across the entire lawn, and I can fine-tune my spreader settings to apply any product at a perfect rate.

Common Mistakes When Using Milky Spore or GrubEx

Overapplication is one of the most common mistakes when using milky spore or GrubEx.

Using too much will just waste product and cost you extra money. Also, using too much GrubEx can damage your soil and remove beneficial organisms that help keep your lawn healthy.

Common Mistakes When Using Milky Spore or GrubEx

GrubEx is great for smaller lawns, as you’ll be able to get the same results with a lower application rate. If you have a larger lawn, milky spore is going to be your best bet. It builds up in the soil over time and provides long-term protection against grubs.

Failing to adjust your spreader for different parts of your lawn is another mistake to avoid. Make sure that you adjust the spreader according to the manufacturer’s instructions. You need to create an even spread across your entire lawn.

One of the biggest mistakes that most people make when applying either product is not watering it in properly. This is essential for both products but especially for GrubEX, which won’t activate until wet.

Investing in a good sprinkler setup is going to be the best bet. It will ensure that your lawn gets the water it needs.

If you don’t have access to a sprinkler, make sure to thoroughly water your lawn with a hose.

Best Practices when Applying Milky Spore or GrubEx

As I mentioned before, you’ve got to protect yourself when applying any lawn care products. It’s especially vital with GrubEx, as it is an insecticide product.

You should wear long sleeves and long pants, a mask, and rubber gloves when putting down your chosen grub-control product.

Best Practices when Applying Milky Spore or GrubEx
Wearing shorts is fine for grass seed, but not recommended for insecticide applications

Dust can form from the friction of the granules. This can cause particles to easily become airborne, and this could be hazardous to your health. I recommend wearing safety glasses, a mask or respirator, and choosing a calm day with little wind for your application.

Always follow the instructions on the label for the best results. Also, make sure to adjust your spreader according to the manufacturer’s instructions.

Take the time you need to follow the guidelines and adjust the spreader correctly.

Which One Should You Choose? Milky Spore vs GrubEx

Making the decision for your lawn between GrubEx and Milky Spore is going to depend on a couple of factors. These include:

  • What type of grubs do you have in your lawn?
  • How long do you plan to live at your current address?
  • How severe and urgent is your grub problem?
  • Do you prefer a lower up-front cost, or value long-term savings?
  • How important is using natural products in your lawn care plan?
Which One Should I Choose Milky Spore or GrubEx

Final Thoughts on Using GrubEx

During the wet season, GrubEx may not be safe for days or even weeks as it needs to dry before the lawn can be used safely.

GrubEx, however, is a much more immediate solution as it doesn’t rely on bacteria establishing in the soil to make the grubs go away. You’ll almost certainly see results within a week of application, and you won’t have any more issues with grubs for up to 4 months.

Final Thoughts on Using Milky Spore

However, if you’re looking for a more long-term solution and want to avoid having to re-apply (after the bacteria has been established), I recommend using milky spore.

It is slower-acting but generally safer on your lawn as it builds up in the soil over time, providing longer-term protection against grubs.

It will take a lot more patience to see the results of applying milky spore, but it is considered to be a much safer product for your lawn overall.

If the grub problem isn’t yet substantial enough for you to consider a product like GrubEx, or you simply want to incorporate natural grub control prevention so you don’t end up with an issue, milky spore is going to be the best option for you.

General Recommendations for Everyone

No matter which product you choose, proper application techniques and following the manufacturer’s instructions are essential for a successful grub control program.

On my lawn, I switched to Milky Spore, as I see it as a safer option that offers significant savings over the long term. I also like that it’s one less thing I now have to think about while maintaining my lawn.

Good luck with your grub control program, and I hope the information I’ve provided here have helped you make your mind about which product to use.

At Lawn Chick, I am committed to publishing accurate, useful, and trustworthy resources for my readers. As part of this commitment, I’ve invited subject matter experts to review our articles for accuracy. I invite you to read our editorial policy and publishing standards which outlines in detail how every article on this site is sourced, edited, fact-checked, and vetted.



Sarah Jameson’s blog, Lawn Chick, is read by over 2 million homeowners each year and she is regularly cited as an expert source of lawn care knowledge by major publications. Her goal is to meet you where you are, and help you achieve a yard you’ll be proud of. Ready to take the next step toward improving your lawn? Grab her free lawn care cheat-sheet: What to Do When - Take the Guesswork Out of Lawn Care, or upgrade your garage by browsing her favorite DIY lawn care products.

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