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Best Crabgrass Killer For St Augustine Grass (2025 Update)

If you’re looking for the best crabgrass killer for St. Augustine grass, it’s important to consider a few factors before making your purchase. First and foremost, you need to ensure that the product you choose is specifically formulated for St. Augustine grass. This type of grass has unique characteristics and requires special care, so using a generic crabgrass killer may do more harm than good. Additionally, you should consider the effectiveness of the product. Look for one that is known for providing long-lasting results and effectively killing crabgrass without harming your St. Augustine grass.

When selecting a crabgrass killer for your St. Augustine grass, it’s also important to consider the application process. Some products require multiple applications or need to be combined with other substances, while others offer a one-step solution. Think about your own level of comfort and preference when it comes to applying the product and choose one that fits your needs.

If you’re unsure about which crabgrass killer to choose, there are a few questions that can help guide your decision. How quickly does the product work? Will it prevent regrowth of crabgrass? Can I apply it myself or should I hire a professional? Is it safe for children or pets? By considering these questions and doing your research, you can be confident in selecting the best crabgrass killer for your St. Augustine grass and enjoy a healthy, weed-free lawn.

10 Best Crabgrass Killer For St Augustine Grass

# Product Image Product Name Product Notes Check Price
1
Ideal for killing weeds and crabgrass on lawns, gardens, and other outdoor areas.
2
The product is ideal for killing common weeds like crabgrass, dandelions, clover, and nutsedge without damaging the lawn.
3
It is ideal for killing crabgrass and other listed weeds in lawns.
4
It is ideal for killing weeds and crabgrass in lawns.
5
This product is ideal for killing weeds and crabgrass in lawns.
6
This product is ideal for preventing crabgrass, chickweed, oxalis, foxtail, and other weeds in lawns up to 5,000 sq. ft.
7
This product is ideal for killing weeds specifically in St. Augustine and Centipede lawns.
8
Ideal for killing weeds in St. Augustine grass and improving the effectiveness of herbicides with a surfactant.
9
This product is ideal for killing crabgrass in lawns.
10
The product is ideal for killing crabgrass and other weeds in lawns or outdoor spaces.
Ideal for killing weeds and crabgrass on lawns, gardens, and other outdoor areas.
The product is ideal for killing common weeds like crabgrass, dandelions, clover, and nutsedge without damaging the lawn.
It is ideal for killing crabgrass and other listed weeds in lawns.
This product is ideal for killing weeds and crabgrass in lawns.
This product is ideal for preventing crabgrass, chickweed, oxalis, foxtail, and other weeds in lawns up to 5,000 sq. ft.
This product is ideal for killing weeds specifically in St. Augustine and Centipede lawns.
Ideal for killing weeds in St. Augustine grass and improving the effectiveness of herbicides with a surfactant.
The product is ideal for killing crabgrass and other weeds in lawns or outdoor spaces.

1. Bioadvanced All-In- One Lawn Weed And Crabgrass Killer, 1.3 Gallon, Ready-To-Use

BioAdvanced presents their All-in-One Formula, a powerful solution for homeowners seeking to eliminate lawn weeds and crabgrass without damage to their lawn. This formula is a weed killer that effectively eradicates over 200 types of listed broadleaf weeds like dandelion and clover, as well as crabgrass.

A unique feature of this product is the SmartTrack Marker, a non-staining red marker that indicates which weeds have been treated and fades with sunlight. This makes it easy to see where the product has been applied, and ensures complete coverage of the affected areas.

Furthermore, this formula is rainproof within just one hour of application, providing reliable protection against sudden rainfall. Please note that this product is not available for sale in Hawaii, Puerto Rico, and Texas. Additionally, the sprayer head may vary from the image provided.

2. Lawn Savior: All-In-One Weed Killer

Introducing a powerful weed killer with an extended wand, designed to simplify the process of spot-treating lawn weeds. With the ability to kill over 250 types of weeds, including dandelion, clover, crabgrass, and yellow nutsedge, this weed killer is a must-have for any homeowner looking to maintain a healthy and beautiful lawn.

Rest assured, this lawn weed killer is completely safe and won't harm your lawn. It's specifically formulated for use on Northern grasses, including Kentucky bluegrass, perennial ryegrass, fescue, bermudagrass, buffalograss, and zoysiagrass.

This potent weed killer starts working immediately, so you can quickly see results. Plus, it's rainproof in as little as 3 hours, ensuring that it stays effective even in inclement weather.

For those hard-to-kill summer crabgrass and grassy weeds, Roundup for Lawns Crabgrass Destroyer is highly recommended.

Investing in this weed killer with an extended wand is a smart choice for any homeowner looking to keep their lawn healthy and weed-free. Say goodbye to stubborn weeds and hello to a lush, green lawn with this powerful weed killer.

3. Bioadvanced Extreme Crabgrass Killer, Ready-To-Spray, 32 Oz

The Crabgrass Killer is an effective solution that targets even the toughest crabgrass strains, including large, hairy, and smooth varieties. Its special formula is designed to penetrate deep into the root, ensuring complete elimination of the weed.

This powerful solution is suitable for use on northern turfs, including Rescue, Perennial Ryegrass, and Kentucky Bluegrass. Whether you have a small lawn or a large yard, this crabgrass killer provides the perfect solution for maintaining a healthy and beautiful lawn.

One of the key features of this product is its rainproof protection. In just one hour, the solution becomes rainproof, ensuring that it remains effective even during wet weather conditions. This means that you can apply it with confidence, knowing that it will provide long-lasting protection against crabgrass.

4. Spectracide Weed Stop For Lawns Plus Crabgrass Killer, Accushot Sprayer, 1.33 Gallon

Looking to get rid of pesky weeds in your lawn? Look no further than Spectracide Weed Stop For Lawns plus crabgrass killer3. With the ability to kill over 470 types of broadleaf and grassy weeds, including dandelion, chickweed, clover, crabgrass, and yellow nutsedge, this product is sure to leave your lawn looking pristine.

One of the best features of this weed killer is that it produces visible results in just 5 hours. This is thanks to its ability to kill weeds by contact and also target their roots. Say goodbye to waiting days or even weeks to see if your weed killer is working.

But don't worry about this powerful weed killer harming your lawn. Spectracide Weed Stop For Lawns plus crabgrass killer3 is specifically designed to kill only listed weeds and not harm your lawn when used as directed. Speaking of directions, for best results, it's recommended to apply this product when temperatures are between 45°F-90°F.

And if for any reason you're not satisfied with this product, Spectracide offers a money-back guarantee. So you can feel confident in your purchase and trust that this weed killer will get the job done. Check the product label for a complete list of weed types that it can kill.

5. Bioadvanced All-In-One Lawn Weed And Crabgrass Killer I, Concentrate, 40 Oz

BioAdvanced's All-in-One formula is the ultimate solution for lawn care. This powerful formula has been specifically designed to eliminate over 200 types of listed broadleaf weeds such as dandelion and clover, as well as crabgrass, without damaging your lawn.

The All-in-One formula is a weed killer that provides effective and long-lasting results. It is a powerful solution that ensures the complete elimination of weeds from your lawn. The formula is designed to work quickly and efficiently, providing results in no time.

The SmartTrack Marker is a unique feature of the All-in-One formula. This non-staining red marker makes it easy to see which weeds have been treated and ensures that no spot is missed. The SmartTrack Marker fades with sunlight, leaving no residue or stains on your lawn.

With the All-in-One formula, you don't have to worry about the weather affecting the effectiveness of the product. The Rainproof Protection feature ensures that the formula is rainproof in just one hour. This means that you can apply it even on rainy days, and the formula will still provide the same level of effectiveness.

6. Weedex With Halts: All-Season Crabgrass Prevention

Scotts WeedEX Prevent with Halts is a highly effective pre-emergent herbicide that provides season-long protection against crabgrass. This innovative formula stops crabgrass before it even has a chance to grow, ensuring that your lawn remains beautiful and healthy all year round.

To use Scotts WeedEX Prevent with Halts, simply apply it in the early spring for season-long prevention of crabgrass. This will also help prevent other grassy and broadleaf weeds such as foxtail, spurge, oxalis, and more. If you missed the early spring application, Fall application is also an option to prevent winter weeds such as poa annua, henbit, and chickweed.

Scotts WeedEX Prevent with Halts is suitable for use on all types of lawns and grass, except for dichondra or bentgrass. This means that no matter what kind of grass you have, you can rely on this product to effectively tackle crabgrass and other weeds.

With its powerful pre-emergent control formula, Scotts WeedEX Prevent with Halts is a must-have for anyone looking to maintain a healthy and beautiful lawn. By preventing the growth of crabgrass and other weeds, this product helps keep your lawn looking lush and green, without the unsightly patches that weeds can cause.

7. Spectracide Weed Stop For Lawns For St. Augustine And Centipede Lawns Concentrate

Introducing the highly effective Weed Killer for St. Augustinegrass and centipedegrass. This remarkable product is designed to eliminate weeds without harming your lush green lawn. With its precise formulation and easy application, you can say goodbye to unsightly weeds and enjoy a beautifully maintained yard.

Say farewell to stubborn weeds such as dollarweed, sandspur, and Florida betony. This powerful weed killer is specifically designed to target and eliminate these established weeds. For a comprehensive list of weeds that it can tackle, please refer to the product label.

Not only does this product eradicate existing weeds, but it also prevents new ones from sprouting. By using this weed killer, you can effectively control weed growth from seeds, ensuring a weed-free lawn for a longer period.

Equipped with the QuickFlip hose-end sprayer, this weed killer offers convenient and hassle-free application. Simply attach it to your garden hose, and with a simple flip of a switch, you're ready to go. No need for complicated mixing or additional equipment. It's that easy!

We understand that you want guaranteed results, and that's precisely what we offer. With our money-back guarantee, you can trust that this weed killer will deliver the desired outcome. For more details on our guarantee, please refer to the product label.

Don't let weeds take over your lawn. Take control with the Weed Killer for St. Augustinegrass and centipedegrass. Experience the satisfaction of a weed-free lawn while keeping your grass healthy and vibrant. Get rid of unsightly weeds and enjoy a beautifully maintained yard with this reliable and efficient weed killer.

8. Atrasurf – Southern Ag Grass Weed Killer Combo

Introducing Product 1, a highly effective weed killer that targets a wide range of broadleaf weeds. This versatile solution is also suitable for use on centipede grass, making it an excellent choice for lawns and gardens. In addition to its weed-killing prowess, Product 1 provides suppression of crabgrass, ensuring a healthy and lush lawn all year round. Whether you're dealing with emerged weeds or those that sprout from seed, this powerful formula is designed to control them all.

When used in conjunction with most pesticides, Product 2 can enhance their effectiveness and deliver even better results. Its unique blend of ingredients works to boost the potency of other treatments, making it ideal for those seeking a more comprehensive approach to pest control.

With its high level of efficacy and broad range of applications, Product 1 and 2 are must-have solutions for any homeowner or gardener looking to maintain a pristine lawn or garden. So why wait? Order your supply today and start enjoying the benefits of a weed-free, pest-free outdoor space!

9. Bayer Advanced 704115a Crabgrass Killer For Lawns, 32 Oz, Ready-To-Spray

The Crabgrass Killer for Lawns is a highly effective solution for eliminating crabgrass and other listed grass weeds, right down to the root. This product is incredibly easy to apply, thanks to its convenient sprayer that connects directly to a garden hose, automatically dispensing the crabgrass killer.

This top-quality crabgrass killer is perfectly safe to use on Kentucky Bluegrass, Perennial Ryegrass and Fescue lawns, and will not cause any harm to the surrounding grass.

One of the standout features of this crabgrass killer is its rainproof protection, which kicks in just one hour after application. This means that even if it starts raining shortly after use, the crabgrass killer will remain effective.

With a coverage area of up to 5,000 square feet, this Crabgrass Killer for Lawns can treat a large area in no time at all. So, whether you're dealing with a small patch of crabgrass or a larger area, this product has you covered.

10. Fertilome (11030) Weed-Out With Crabgrass Killer (16 Oz)

The Selective Weed Killer is a powerful solution that can effectively control over 200 types of grassy and broadleaf weeds, such as Crabgrass and Foxtail. It is specifically designed for use on established lawns, including Bermuda, Buffalo, Kentucky Bluegrass, and other types.

This 16-ounce bottle of liquid concentrate weed killer is capable of treating up to 2,500 square feet of lawn area, making it a cost-effective solution for weed control. However, it is important to note that applying the weed killer to bermudagrass may cause temporary yellowing or discoloration. Nonetheless, full recovery is expected, and the lawn will return to its normal color in no time.

To achieve optimum results, it is recommended to apply the Selective Weed Killer during the spring or early summer when weeds are small and actively growing. This ensures that the weeds are at their most vulnerable state, making the weed killer more effective in controlling them.

Best Crabgrass Killer For St Augustine Grass FAQs

Are there any natural or organic options available for killing crabgrass in St. Augustine grass?

Yes, there are natural and organic options available for killing crabgrass in St. Augustine grass. Here are a few suggestions:

1. Hand pulling: Although labor-intensive, manually pulling out crabgrass can be an effective method, especially for small infestations. Ensure that you remove the entire plant, including the roots.

2. Organic herbicides: Look for herbicides that are labeled as organic or natural and specifically mention crabgrass control. These products often contain ingredients like vinegar, citric acid, or essential oils. Follow the instructions carefully for best results.

3. Corn gluten meal: This natural weed suppressant can help prevent crabgrass from germinating. It works by inhibiting root development in young seedlings. Apply corn gluten meal in early spring before crabgrass starts to germinate.

4. Improve lawn health: Maintaining a healthy and dense St. Augustine grass can naturally suppress crabgrass growth. Regularly fertilize, water, and mow your lawn at the proper height to promote healthy grass and discourage weed growth.

Remember that natural and organic methods may require multiple applications and may not be as fast-acting as synthetic herbicides. Persistence and regular maintenance are key to effectively controlling crabgrass in St. Augustine grass.

Are there any precautions or safety measures to take when using a crabgrass killer on St. Augustine grass?

When using a crabgrass killer on St. Augustine grass, it is important to take some precautions to ensure the safety of your lawn. Here are a few measures you can take:

1. Read the instructions: Always carefully read and follow the instructions provided by the manufacturer. This will give you valuable information about the application rate, timing, and safety precautions specific to the crabgrass killer you are using.

2. Spot treat: Instead of applying the crabgrass killer over the entire lawn, consider spot treating only the affected areas. This will minimize the exposure of St. Augustine grass to the herbicide.

3. Timing: Choose the right time to apply the crabgrass killer. Ideally, apply it during the early spring or fall when the St. Augustine grass is actively growing and the crabgrass is young and vulnerable. Avoid applying during periods of drought or extreme heat, as it can stress the grass.

4. Watering: Water your lawn thoroughly before applying the crabgrass killer. This will help the herbicide penetrate the soil and reach the crabgrass roots effectively.

5. Avoid drift: Be cautious of any wind when applying the herbicide, as it may cause the product to drift onto desirable plants. Consider using a handheld sprayer or a shield to prevent drift.

If you are unsure about using a crabgrass killer on St. Augustine grass, it is always a good idea to consult with a lawn care professional or contact the manufacturer for specific recommendations.

Are there any specific application techniques or timings to consider when using a crabgrass killer on St. Augustine grass?

When using a crabgrass killer on St. Augustine grass, it is important to follow specific application techniques and timings to ensure the best results without damaging your lawn. Here are some guidelines to consider:

1. Timing: Apply the crabgrass killer when the weed is actively growing and before it reaches maturity. This is usually in the spring or early summer, depending on your region. Avoid applying during hot weather or when your lawn is under stress, as this can increase the risk of damage.

2. Temperature: Check the product label for temperature restrictions. Some crabgrass killers may not be effective or may harm St. Augustine grass if applied in extreme temperatures. Aim for a temperature range that is suitable for both the product and your lawn.

3. Application technique: Follow the instructions on the product label for the recommended application rate and method. Most commonly, crabgrass killers are applied as a liquid spray or granules. Ensure even coverage and avoid overlapping or missing spots.

4. Watering: After applying the crabgrass killer, water your lawn lightly to activate the product and ensure it reaches the weed's roots. Follow the instructions on the label regarding post-application watering.

5. Post-emergent control: If crabgrass has already emerged, you may need to consider a post-emergent crabgrass killer specifically formulated for St. Augustine grass. These products are designed to target crabgrass without harming your lawn.

Always read and follow the instructions provided by the manufacturer for the specific crabgrass killer you are using. If you are unsure about the application techniques or timings, consider consulting with a professional lawn care service for guidance.

Are there any specific brands or products that are recommended as the best crabgrass killer for St. Augustine grass?

When it comes to selecting a crabgrass killer for St. Augustine grass, there are a few specific brands and products that are often recommended by professionals and homeowners. One popular option is the Southern Ag 2, 4-D Amine Weed Killer, which is known for effectively controlling crabgrass without harming St. Augustine grass. Another widely used product is the Drive XLR8 Herbicide, which is specifically designed to target crabgrass and other broadleaf weeds while being safe for St. Augustine grass.

Additionally, there are several selective herbicides that contain the active ingredient quinclorac, such as Ortho Weed B Gon Weed Killer for St. Augustine Grass. These products are known for their ability to control crabgrass and other weeds without damaging St. Augustine grass. It's important to carefully read and follow the instructions on the product label to ensure proper application and safety.

While these are some recommended options, it is always a good idea to consult with a local lawn care professional or your local agricultural extension office for specific recommendations tailored to your region and the condition of your St. Augustine grass.

Can a crabgrass killer also prevent future crabgrass growth in St. Augustine grass?

While crabgrass killers are primarily designed to eliminate existing crabgrass, some products also have pre-emergent properties that can help prevent future crabgrass growth. However, it is crucial to check the label and make sure that the specific crabgrass killer you are using is safe for St. Augustine grass. St. Augustine grass has different growth patterns and tolerances compared to other grass types, so using a product that is not specifically formulated for it may harm your lawn.

To prevent future crabgrass growth in St. Augustine grass, it is recommended to focus on maintaining a healthy lawn through proper watering, mowing, and fertilizing practices. These practices promote thick turf, which can help prevent crabgrass from taking hold. Additionally, overseeding with St. Augustine grass in bare or thin areas can also help prevent weed growth.

If you are unsure about which specific products to use or need further guidance, it is always wise to consult with a local lawn care professional or your local cooperative extension service for personalized recommendations based on your region and specific lawn conditions.

Can a pre-emergent herbicide be used as a crabgrass killer for St. Augustine grass?

No, a pre-emergent herbicide cannot be used as a crabgrass killer for St. Augustine grass. Pre-emergent herbicides are specifically designed to prevent weed seeds from germinating, and they work by creating a barrier on the soil surface. They are effective in controlling crabgrass by stopping its seeds from sprouting. However, once crabgrass has already emerged, pre-emergent herbicides lose their effectiveness in killing it.

To effectively control crabgrass in St. Augustine grass, a post-emergent herbicide that specifically targets crabgrass should be used. There are several selective herbicides available that are formulated to kill crabgrass without harming St. Augustine grass. It is important to carefully read and follow the instructions on the herbicide label to ensure proper application and avoid any damage to the desired turfgrass.

If you are unsure about which herbicide to use or need more specific recommendations, it is always advisable to consult with a professional lawn care specialist or your local agricultural extension office for guidance.

How long does it take for a crabgrass killer to start showing results on St. Augustine grass?

The time it takes for a crabgrass killer to show results on St. Augustine grass can vary depending on several factors. Generally, most crabgrass killers start working within a few days to a week. However, it is important to note that complete eradication may take longer.

Factors such as the specific product used, the severity of the crabgrass infestation, and the weather conditions can all influence the speed of results. Some crabgrass killers may require multiple applications over several weeks to effectively control the weed.

To ensure the best results, it is important to carefully follow the instructions provided by the manufacturer. Additionally, maintaining proper lawn care practices, such as regular mowing, watering, and fertilizing, can help prevent future crabgrass growth and promote the health of your St. Augustine grass. If you are unsure about the specific product or application process, it is always a good idea to consult with a professional or seek advice from a local garden center.

Is it safe to use a crabgrass killer on St. Augustine grass without causing damage to the lawn?

Using a crabgrass killer on St. Augustine grass can be risky as St. Augustine grass is sensitive to certain herbicides. While some crabgrass killers are labeled as safe for use on St. Augustine grass, it is important to carefully read and follow the instructions on the product label. Additionally, it is advisable to conduct a small test area application before treating the entire lawn to ensure that the crabgrass killer does not cause any damage.

Alternatively, manual removal of crabgrass can be a safer option for St. Augustine grass. This involves pulling the weeds by hand or using a weeding tool to avoid damaging the lawn. Regular mowing, proper watering, and maintaining a healthy lawn can also help prevent crabgrass growth.

If you are uncertain about using a crabgrass killer on St. Augustine grass, it is recommended to consult with a professional lawn care service or a local garden center for specific recommendations tailored to your lawn's needs.

What are the key ingredients to look for in a crabgrass killer for St. Augustine grass?

When looking for a crabgrass killer specifically for St. Augustine grass, there are a few key ingredients to consider. Firstly, ensure that the product contains an active ingredient called quinclorac. Quinclorac is effective in controlling crabgrass in St. Augustine grass without causing harm to the turf itself. It is selective and won't damage your lawn when used as directed.

Additionally, check if the product contains other selective herbicides like fenoxaprop-p-ethyl or sethoxydim. These ingredients target grassy weeds, including crabgrass, while leaving your St. Augustine grass unharmed.

It's important to follow the instructions on the product label carefully, including the recommended application rates and timing. Applying the crabgrass killer at the right time, usually in spring or early summer, when the crabgrass is actively growing, will increase the effectiveness of the product.

If you are unsure about the specific brands or products available in your local market, it is always a good idea to consult with a local gardening expert or a professional at your nearest garden center. They can provide you with personalized recommendations based on your region and the specific needs of your St. Augustine grass.

What is the most effective crabgrass killer for St. Augustine grass?

When it comes to controlling crabgrass in St. Augustine grass, it is important to choose a selective herbicide that specifically targets crabgrass while being safe for use on St. Augustine grass. One of the most effective crabgrass killers for St. Augustine grass is a herbicide containing the active ingredient sethoxydim. Sethoxydim is a post-emergent herbicide that targets grassy weeds like crabgrass while leaving St. Augustine grass unharmed.

Products like Ortho Weed B Gon Weed Killer for St. Augustine Grass plus Crabgrass Control or Bayer Advanced All-in-One Lawn Weed & Crabgrass Killer are good options to consider. These products are designed to effectively control crabgrass while also providing broad-spectrum weed control.

It is important to carefully read and follow the instructions on the product label to ensure proper application and safety. Additionally, maintaining a healthy lawn through regular mowing, watering, and fertilizing can help prevent crabgrass from taking hold in the first place.