Trust me, I’ve been in your shoes with a weed-infested lawn. It’s frustrating to watch them take over your beautiful grass, turning lush green into a patchy, unkempt mess. For years, I battled everything from stubborn crabgrass to persistent dandelions, trying countless products with mixed results. This led me on a dedicated quest to personally test and discover the best post emergent weed killer for lawns. Here’s what I learned through hands-on experience, hours of observation, and the occasional lawn emergency.
1. Ortho WeedClear Lawn Weed Killer Ready-To-Spray – Kills Crabgrass
One spring, as crabgrass began its relentless invasion across my Kentucky Bluegrass, I knew I needed a quick, straightforward solution. This Ortho WeedClear ready-to-spray product caught my eye because of its promise of easy application and broad-spectrum killing power, especially for that unwelcome grassy weed. I wanted to see if its convenience matched its effectiveness.
Key Features:
– Hose-End Application: This makes it incredibly easy to cover large areas without mixing or separate sprayers, saving valuable time.
– Fast-Acting Weed Control: It claims visible results quickly, which is crucial when you want to stop weeds before they spread further.
– Extensive Coverage (5,000 sq ft): A single bottle handles a significant portion of my yard, making it cost-effective for medium to large lawns.
– Targets Young, Actively Growing Weeds: This feature emphasizes the importance of timing your application for maximum efficacy.
– Lawn-Friendly Formula: It’s designed to kill weeds without harming common lawn grasses like Fescue and Zoysiagrass, protecting your desired turf.
Performance & Real-World Use
Hooking this up to my garden hose was as simple as the instructions claimed. I walked my lawn methodically, ensuring even coverage. Within two days, the crabgrass and dandelions started showing signs of distress—wilting and yellowing. The speed was impressive, particularly on the younger weeds. I saw significant die-back within a week, and the grass remained unharmed.
Pros:
– Effortless Application: The hose-end sprayer is genuinely convenient and mess-free.
– Visible Results Quickly: Weeds begin to wilt and yellow within a day or two, providing quick satisfaction.
– Safe for Many Grass Types: It controlled weeds effectively without damaging my cool-season grass.
– Good Coverage Area: A single bottle goes a long way for typical suburban lawns.
Cons:
– Requires Active Growth: Less effective on dormant or mature, hardened weeds.
– Limited Residual Control: It kills existing weeds but doesn’t prevent new ones from sprouting later.
– Hose Pressure Dependent: Performance can vary slightly depending on your home’s water pressure.
Who Should Buy This:
This is an excellent choice for homeowners with medium to large lawns who need a fast, convenient, and effective solution for common broadleaf and grassy weeds without the hassle of mixing chemicals. It’s perfect for those who prefer a ready-to-use system.
My Verdict:
For sheer ease of use and respectable efficacy against a wide range of common lawn weeds, especially younger ones, this Ortho WeedClear product is a solid contender. It delivers on its promise of quick results and not harming the grass, which is a major win in my book. It’s my go-to for general weed clean-up when time is of the essence. I’d give it an 8.5/10 for its category.
2. Southern Ag Amine 2,4-D WEED KILLER, 32oz – Quart
When I encountered a widespread invasion of broadleaf weeds—think dandelions, clover, and plantain—across a larger, less manicured section of my property, I knew I needed something potent and economical. The Southern Ag Amine 2,4-D came highly recommended by fellow lawn enthusiasts for its concentrated power and versatility. My goal was to see if this professional-grade concentrate could tackle those tough weeds without breaking the bank.
Key Features:
– Low, Economical Use Rate: This means a little goes a very long way, offering significant cost savings for large areas.
– Controls Many Broadleaf Weeds & Woody Plants: Its broad spectrum against a variety of tough weeds makes it highly versatile.
– Versatile Application Areas: It’s not just for turf; its label allows use in pastures, rangeland, and even fence lines, showcasing its robust nature.
– Concentrated Formula: Requires mixing, which allows for precise control over application strength.
– Systemic Action: Absorbed by the weed and transported throughout, ensuring a complete kill down to the root.
Performance & Real-World Use
Mixing this concentrate required careful measurement and a dedicated sprayer, which is a step up from ready-to-use options. I applied it to a particularly stubborn patch of clover and dandelions in late spring. Within a week, the weeds started to curl and turn black, indicating a thorough systemic kill. It was slower acting than some ready-to-spray products, but the results were undeniably comprehensive, even on mature weeds.
Pros:
– Highly Economical: A single bottle can treat very large areas, offering excellent value.
– Extremely Effective: It thoroughly eradicates a wide range of tough broadleaf weeds down to the root.
– Flexible Application: Can be used in various settings beyond just manicured lawns.
– Professional-Grade Power: Delivers the kind of results a lawn care professional would expect.
Cons:
– Requires Mixing: Not a ready-to-use product, demanding more effort and precision.
– Slower Visible Results: Takes longer for weeds to fully die compared to some fast-acting solutions.
– Potential for Drift: Requires careful application to avoid harming desirable plants nearby.
Who Should Buy This:
This is ideal for experienced lawn care enthusiasts or those with large properties, pastures, or tough weed infestations who are comfortable with mixing concentrates. It’s perfect if you prioritize cost-effectiveness and comprehensive broadleaf weed control over immediate visible results and ready-to-use convenience.
My Verdict:
For tackling extensive broadleaf weed issues with professional-grade effectiveness and an incredibly economical price point, Southern Ag Amine 2,4-D is simply outstanding. It might require a bit more effort to prepare, but the results speak for themselves. If you need serious weed control on a budget for larger areas, this is your champion. I rate it a strong 9/10 for its power and value.
3. Scotts Weed Control for Lawns (Northern), 14 lb.
After a particularly wet spring, my Northern lawn was suddenly awash with dandelions and clover. I usually prefer liquid applications, but the sheer density of weeds made me consider a granular approach. I picked up Scotts Weed Control for Lawns (Northern) because I’ve had good experiences with Scotts’ fertilizers, and I wanted to see if their granular weed control lived up to the hype for broadleaf weeds.
Key Features:
– Kills Toughest Weeds (Dandelion, Clover): Specifically formulated to target those very common and persistent broadleaf invaders.
– Controls Over 200 Weed Types: This broad spectrum makes it a versatile option for general weed control in Northern lawns.
– Starts Working on Contact: While granular products aren’t always instantaneous, this one promises fairly quick initial action.
– Kills the Root: Ensures that weeds are eradicated permanently and don’t grow back from remaining root fragments.
– Granular Weed Control: Offers a different application method, often preferred by those who don’t want to spray liquids.
Performance & Real-World Use
I applied this product using a broadcast spreader on a dewy morning, as the instructions suggested, to ensure the granules would stick to the weed leaves. This was crucial for contact. Within a few days, I saw the broadleaf weeds starting to curl and darken. The granular nature meant I didn’t get instant gratification like with some liquids, but the widespread coverage was excellent. My grass remained healthy, showing no signs of stress, while the weeds slowly disappeared over two weeks.
Pros:
– Easy Spreader Application: Simple to apply evenly across large areas with a standard broadcast spreader.
– Excellent for Broadleaf Weeds: Very effective against common weeds like dandelions and clover.
– Won’t Harm Lawn Grass: Specifically designed to target weeds without damaging established turf.
– Kills Down to the Root: Provides long-term eradication of existing weeds.
Cons:
– Requires Dewy Conditions: Best applied when grass is wet, limiting application times.
– Slower Acting: Takes longer to see full results compared to some liquid herbicides.
– Less Effective on Grassy Weeds: Primarily focused on broadleaf weeds, not ideal for crabgrass.
Who Should Buy This:
This product is perfect for homeowners with Northern lawns who prefer a granular application method for widespread broadleaf weed control. If you have a large lawn and want to use a spreader for even coverage, and you’re battling dandelions and clover, this is a strong contender.
My Verdict:
Scotts Weed Control for Lawns is a reliable, easy-to-apply granular solution for common broadleaf weeds in Northern climates. While it might not be the fastest, its effectiveness against dandelions and clover, coupled with its lawn-safe formula, makes it a staple for many. For its specific application and target weeds, it earns a respectable 7.8/10.
4. Ortho WeedClear Weed Killer for Lawns with Comfort Wand
Dealing with targeted weed patches or stray dandelions can be a pain with a regular sprayer. I often found myself pumping a sprayer repeatedly, only for my hand to cramp before I finished. When I saw the Ortho WeedClear with Comfort Wand, I was immediately intrigued by the “no pumping required” claim. I wanted to see if this applicator truly made spot treatment and precision weed control as effortless as it sounded.
Key Features:
– Lawn Friendly Formula: Contains three proven ingredients specifically designed to target weeds without harming grass when used correctly.
– Easy Continuous Spray Comfort Wand: This is the game-changer, offering a consistent spray without manual pumping, reducing hand fatigue.
– Kills Over 250 Weeds: A very broad spectrum, tackling a huge variety of broadleaf weeds from dandelions to poison ivy.
– Fast Visible Results (in hours): Promises quick action, which is satisfying for immediate weed control.
– Rainproof in 1 Hour: This means less worry about a sudden downpour washing away your efforts shortly after application.
Performance & Real-World Use
The Comfort Wand lived up to its name. Pressing the button and getting a continuous, fine spray was a revelation for spot treating. I walked around my lawn, easily targeting individual weeds without bending or getting tired. Visible results were indeed rapid; I saw wilting on dandelions and clover within a few hours. The precision allowed me to hit weeds tucked near flower beds without overspray concerns, making it incredibly efficient for detailed work.
Pros:
– Effortless Spot Treatment: The Comfort Wand is a standout feature, making targeted applications a breeze.
– Rapid Visual Effect: Weeds show signs of dying very quickly, often within hours.
– Broad Weed Spectrum: Effectively kills a vast array of common broadleaf weeds.
– Rainproof Quickly: Reduces anxiety about weather interference after application.
Cons:
– Limited Coverage for Large Areas: Not practical for entire lawn treatments due to its spot-treatment design.
– Battery Life: The wand requires batteries, which need occasional replacement.
– Higher Cost per Ounce: More expensive than concentrates, but you’re paying for convenience.
Who Should Buy This:
This product is ideal for homeowners who need precise, easy, and fast spot treatment for individual weeds or small weed patches in their lawn. If you hate pumping traditional sprayers and want immediate visual results on a wide range of broadleaf weeds, this is an excellent choice.
My Verdict:
The Ortho WeedClear with Comfort Wand is a fantastic innovation for targeted weed control. Its ease of use and rapid results make it my top pick for maintaining a pristine lawn by quickly eliminating nuisance weeds. While not for full-lawn coverage, it excels in its niche. I rate it an impressive 9/10 for convenience and effectiveness in spot treatment.
5. BASF Drive XLR8 Crabgrass Killer for Lawn and Turf Concentrate
My ongoing battle with crabgrass led me to explore more professional-grade options. While some products offered decent control, I was looking for something with superior efficacy and residual control, particularly for those tough, mature crabgrass clumps. The BASF Drive XLR8, known in the professional landscaping world, promised precisely that. I was determined to see if this concentrate could finally win the war against the notorious grassy weed.
Key Features:
– Water-Based Formulation: Ensures faster plant uptake and superior control, enhancing its effectiveness.
– Extended Residual Control (up to 30 days): This feature means it keeps working to prevent new weed emergence for a longer period, reducing repeat applications.
– Broad-Spectrum Weed Control: Targets a wide range of grassy weeds like crabgrass, foxtail, and kikuyu grass, as well as several broadleaf weeds.
– Versatile Application: Labeled for use on both warm and cool-season turf, making it adaptable to various lawn types.
– Rainfast in Less Than an Hour: Crucial for ensuring the product isn’t washed away by unexpected rain after application.
Performance & Real-World Use
Mixing Drive XLR8 required careful attention to detail, donning appropriate PPE as recommended. I applied it to a particularly dense infestation of mature crabgrass. Within a week, the crabgrass began to yellow and die back dramatically. What truly impressed me was its residual action; new crabgrass wasn’t popping up in the treated areas for weeks afterward. It was clear this wasn’t just a quick kill; it was a comprehensive suppression, and my Fescue lawn showed no signs of stress.
Pros:
– Exceptional Crabgrass Control: Hands down one of the most effective products I’ve used for crabgrass, even mature plants.
– Excellent Residual Action: Provides ongoing weed suppression, reducing subsequent weed growth.
– Fast Rainfastness: Minimizes concerns about rain washing away the product after application.
– Broad-Spectrum Efficacy: Tackles multiple tough grassy and broadleaf weeds effectively.
Cons:
– Higher Cost: A professional-grade product comes with a higher price tag.
– Requires PPE and Mixing: Not a ready-to-use option, demanding more careful handling and preparation.
– Professional Product: May be overkill for light weed issues or small lawns.
Who Should Buy This:
This product is for the serious lawn care enthusiast, professional landscaper, or homeowner facing a significant and persistent crabgrass problem. If you need powerful, long-lasting control over tough grassy weeds and some broadleaves, and you’re comfortable with concentrate mixing and safety precautions, this is the ultimate solution.
My Verdict:
BASF Drive XLR8 is a powerhouse for crabgrass control. Its effectiveness, residual action, and versatility make it a top-tier choice for those who demand the best in challenging situations. While it requires more effort and investment, the results are unparalleled. For serious weed eradication and ongoing prevention, I confidently give it a 9.5/10.
6. Scotts Liquid Turf Builder with Plus 2 Weed & Feed
Sometimes, my lawn needs a pick-me-up and a weed killer at the same time. I’d heard about weed and feed products, but often wondered if they truly delivered on both fronts without compromising either. Scotts Liquid Turf Builder with Plus 2 Weed & Feed seemed like a convenient way to tackle two tasks simultaneously. I decided to try it on a section of my lawn that was looking a bit lackluster and had a scattering of dandelions and chickweed.
Key Features:
– Fertilizes in 24 Hours while Controlling Weeds: This dual action is its primary appeal, saving time and effort.
– Kills Dandelions, Clover, and Other Major Lawn Weeds: Targets a significant list of common broadleaf weeds.
– Easy to Use, Simply Attach Hose and Spray: Similar to other hose-end products, it offers convenient application.
– Works on a Wide Range of Broadleaf Weeds: Includes buckhorn, ground ivy, henbit, poison ivy, and spurge, making it versatile.
– Spray When Weeds Are Actively Growing: Emphasizes proper timing for maximum effectiveness of the weed-killing agents.
Performance & Real-World Use
Applying this product was straightforward, just like the other hose-end sprays. I focused on a part of my lawn that was showing some light yellowing and had a fair amount of clover. Within a couple of days, the grass took on a noticeably richer green hue—the “Turf Builder” part definitely worked quickly. Simultaneously, the clover and dandelions started to curl and die back. It was satisfying to see both improvements happening in tandem. It didn’t obliterate the toughest weeds as quickly as a dedicated herbicide, but it certainly made a difference.
Pros:
– Dual Action (Feed & Weed): Simplifies lawn care by addressing nutrition and weed control in one step.
– Convenient Application: The hose-end sprayer makes it very easy to apply across the lawn.
– Visible Fertilization Results: Grass often shows a greener appearance within a day or two.
– Effective on Common Broadleaf Weeds: Tackles a good range of typical lawn invaders.
Cons:
– Less Potent Weed Killer: Not as strong as dedicated weed killers for very tough or dense infestations.
– Timing Can Be Tricky: Optimal timing for feeding might not perfectly align with optimal timing for weed killing.
– Not for Grassy Weeds: Primarily targets broadleaf weeds, so it won’t help with crabgrass.
Who Should Buy This:
This product is excellent for homeowners looking for a simple, convenient way to give their lawn a boost of nutrients while simultaneously controlling common broadleaf weeds. It’s ideal for routine lawn maintenance and minor weed issues, rather than severe infestations.
My Verdict:
Scotts Liquid Turf Builder with Plus 2 Weed & Feed is a solid choice for those who appreciate the efficiency of a two-in-one product. It effectively improves grass color and tackles many broadleaf weeds, making it a valuable part of a regular lawn care routine. It’s a great option when you want convenience and a noticeable improvement in overall lawn health and appearance. I rate it 7.5/10 for its specific niche.
Comparison Insights: My Top 3 Picks
Throughout my extensive testing journey, three products consistently stood out for their performance, specific strengths, and overall value. Here’s a detailed look at how they stack up against each other, highlighting their key differences and ideal scenarios.
My top three picks are: BASF Drive XLR8 Crabgrass Killer, Southern Ag Amine 2,4-D WEED KILLER, and Ortho WeedClear Weed Killer for Lawns with Comfort Wand.
BASF Drive XLR8 Crabgrass Killer for Lawn and Turf Concentrate:
- Weed Focus: Unmatched for crabgrass and tough grassy weeds, with excellent broadleaf control as a bonus.
- Application: Requires careful mixing and a separate sprayer, making it less convenient for quick jobs but highly adaptable.
- Speed: Visible results within a week, but its real power is the long-lasting residual control (up to 30 days), which sets it apart.
- Value: Highest upfront cost but offers professional-grade efficacy and long-term prevention, making it economical in the long run for severe issues.
- Ideal User: Serious lawn enthusiasts or professionals dealing with persistent crabgrass or other tough grassy weeds across various turf types.
Southern Ag Amine 2,4-D WEED KILLER, 32oz – Quart:
- Weed Focus: Exceptional for a wide range of broadleaf weeds, including dandelions, clover, and plantain. Not designed for grassy weeds.
- Application: A concentrate that requires mixing, offering precise control over strength and highly economical for large areas.
- Speed: Slower acting than some ready-to-spray options, taking 1-2 weeks for full eradication, but very thorough.
- Value: Incredibly economical for its potency. A single quart treats vast areas, making it the most cost-effective solution for widespread broadleaf problems.
- Ideal User: Homeowners with large properties or severe broadleaf infestations who prioritize cost-effectiveness and comprehensive eradication over immediate gratification.
Ortho WeedClear Weed Killer for Lawns with Comfort Wand:
- Weed Focus: Excellent for spot-treating a very broad spectrum of common broadleaf weeds (over 250 types), like dandelions and chickweed.
- Application: Ready-to-use with a continuous spray Comfort Wand, offering unparalleled ease and precision for targeted application. No mixing or pumping required.
- Speed: Fastest visible results, often within hours, making it incredibly satisfying for quick clean-ups. Rainproof in just one hour.
- Value: Higher cost per ounce compared to concentrates, but the convenience and precision are its main selling points. Best for managing smaller areas.
- Ideal User: Homeowners who need fast, easy, and precise spot treatment for individual weeds or small patches without the effort of traditional sprayers.
In essence, if you’re battling stubborn crabgrass, reach for the BASF Drive XLR8. For widespread broadleaf invasions on a budget, Southern Ag Amine 2,4-D is your champion. And for quick, effortless spot treatment of those pesky individual weeds, the Ortho WeedClear with Comfort Wand is simply unbeatable. Each offers a distinct advantage, making them my go-to solutions for different lawn challenges.
Final Verdict
Navigating the world of post-emergent weed killers can be daunting, but my journey through hands-on testing has illuminated the true strengths of various products for different lawn scenarios. There’s no single “best” for every situation, but rather the right tool for the job.
For the homeowner battling the tenacious enemy that is crabgrass, especially mature clumps or widespread infestations, my unequivocal recommendation goes to BASF Drive XLR8 Crabgrass Killer. It’s a professional-grade solution that delivers unparalleled results, effectively eradicating crabgrass down to the root and offering crucial residual control. While it requires careful mixing and a bit more investment, its power and long-term effectiveness make it a game-changer for serious crabgrass problems.
When it comes to widespread broadleaf weeds like dandelions, clover, and plantain across larger properties, the Southern Ag Amine 2,4-D WEED KILLER stands out. Its concentrated formula provides incredible value, allowing you to treat vast areas economically. It’s potent and thorough, ensuring a complete kill of those stubborn broadleaf invaders, making it the best choice for comprehensive broadleaf control on a budget.
And for those routine touch-ups, where a few dandelions or patches of clover pop up, Ortho WeedClear Weed Killer for Lawns with Comfort Wand is the undisputed champion of convenience and precision. The continuous spray wand is a revelation, transforming tedious spot treatment into an effortless task with rapid visible results. It’s perfect for maintaining a pristine lawn with minimal fuss.
Here’s a quick summary of my top recommendations based on specific needs:
- For the Toughest Crabgrass: BASF Drive XLR8 Crabgrass Killer
- For Widespread Broadleaf Weeds (Value Pick): Southern Ag Amine 2,4-D WEED KILLER
- For Easy, Precise Spot Treatment: Ortho WeedClear Weed Killer for Lawns with Comfort Wand
- For General Broadleaf & Crabgrass (Ready-to-Spray): Ortho WeedClear Lawn Weed Killer Ready-To-Spray
- For Weed Control + Fertilization: Scotts Liquid Turf Builder with Plus 2 Weed & Feed
- For Granular Broadleaf Control (Northern Lawns): Scotts Weed Control for Lawns (Northern)
Ultimately, success in weed control hinges on understanding your specific weed problem, your lawn type, and your comfort level with application methods. By choosing one of these tested and proven products, you’ll be well-equipped to reclaim your lawn from unwelcome invaders.
Buying Guide: Choosing Your Post Emergent Weed Killer
Selecting the right post-emergent weed killer can feel like navigating a maze of options. Based on my experience, understanding a few key factors will help you make the best choice for your lawn.
1. Identify Your Weeds
Before you even think about buying, you need to know your enemy. Are you battling broadleaf weeds like dandelions, clover, plantain, or ground ivy? Or are grassy weeds like crabgrass, foxtail, or quackgrass the problem? Many post-emergent herbicides are selective, meaning they target one type of weed without harming your lawn grass. A product excellent for broadleaf weeds might be useless against crabgrass, and vice-versa. Some, like BASF Drive XLR8, offer a broader spectrum, but specificity often leads to higher efficacy. Take the time to identify the weeds plaguing your lawn; a simple online search with a picture of the weed can go a long way.
2. Consider Your Lawn Type and Size
Your grass type is crucial. Most products are formulated to be safe for common lawn grasses like Kentucky Bluegrass, Fescue, Zoysiagrass, or Bermudagrass. However, some herbicides might harm certain sensitive grass types. Always read the label carefully to ensure compatibility with your specific lawn. Additionally, consider the size of your lawn. For small lawns or spot treatments, a ready-to-use spray with a wand (like Ortho WeedClear with Comfort Wand) offers convenience. For medium to large lawns or widespread infestations, a hose-end concentrate (like Ortho WeedClear Ready-To-Spray) or a concentrate requiring mixing (like Southern Ag Amine 2,4-D or BASF Drive XLR8) will be more economical and efficient for covering large areas. Granular products (like Scotts Weed Control for Lawns) are also excellent for larger areas when applied with a spreader.
3. Application Method & Convenience
How do you prefer to apply weed killer?
* Ready-to-Use Sprays (e.g., Ortho WeedClear with Comfort Wand): The easiest and most convenient for spot treating or small areas. No mixing required, just point and spray.
* Hose-End Sprays (e.g., Ortho WeedClear Ready-To-Spray, Scotts Liquid Turf Builder with Plus 2 Weed & Feed): Attach directly to your garden hose, ideal for medium to large lawns where you want even coverage without the fuss of a pump sprayer.
* Concentrates (e.g., Southern Ag Amine 2,4-D, BASF Drive XLR8): Require mixing with water in a separate tank sprayer. Best for large areas, offering the most control over dilution rates and often the most potent and cost-effective per square foot. They demand more effort but deliver professional-grade results.
* Granular Products (e.g., Scotts Weed Control for Lawns): Applied with a broadcast or drop spreader. Excellent for large lawns and can sometimes combine weed control with fertilization. Often require application on a dewy lawn for best results.
Your comfort level with mixing chemicals and handling equipment should guide your choice here.
4. Speed of Results & Environmental Factors
Are you looking for instant gratification or long-term control? Some products, especially those for spot treatment, boast “visible results in hours.” Others, particularly concentrates that work systemically, might take a week or two to show full effect but offer a more thorough, root-killing action. Also, consider the weather. Products that are “rainproof in 1 hour” offer flexibility if you live in an area prone to sudden rain showers. Always check the label for optimal temperature ranges for application; applying outside these ranges can reduce effectiveness or even harm your lawn. Finally, be mindful of nearby desirable plants, shrubs, and trees; overspray from certain herbicides can cause damage.
FAQ Section
Q: What exactly is a “post-emergent” weed killer?
A: A post-emergent weed killer is designed to kill weeds that have already sprouted and are actively growing. Unlike pre-emergent herbicides which prevent weed seeds from germinating, post-emergents target visible weeds after they’ve emerged from the soil. They are your solution for existing weed problems.
Q: Can I apply post-emergent weed killer to my entire lawn?
A: Many post-emergent weed killers are selective, meaning they target weeds without harming common lawn grasses when used as directed. Products like Ortho WeedClear are designed for full lawn application. However, always check the product label to ensure it’s safe for your specific grass type and intended use.
Q: How long does it take for post-emergent weed killers to work?
A: The timeframe varies greatly by product and weed type. Some fast-acting formulas, especially for broadleaf weeds, can show visible results (wilting, yellowing) within hours to a couple of days. Others, particularly concentrates that work systemically, might take 1-2 weeks for weeds to fully die back.
Q: Is it safe for pets and children to be on the lawn after application?
A: Most manufacturers recommend keeping pets and children off the treated area until the spray has completely dried. This usually takes a few hours. Always consult the specific product label for detailed safety instructions and re-entry intervals, as these can vary.
Q: What is the best time of year to apply post-emergent weed killer?
A: The best time is when weeds are young and actively growing, usually in spring and fall. Applying during periods of extreme heat or drought can stress your lawn and make the herbicide less effective. For specific weeds like crabgrass, timing is critical, often needing application when temperatures are consistently warm.
Q: What’s the difference between selective and non-selective weed killers?
A: Selective weed killers (like those reviewed here) target specific weeds without harming desirable plants, such as your lawn grass. Non-selective weed killers, like glyphosate, kill almost any plant they contact, including grass. Always use selective products on your lawn.
Q: Do I need to water my lawn before or after applying post-emergent weed killer?
A: This depends entirely on the product. Some granular products require a dewy or lightly wet lawn for the granules to stick to weed leaves. Liquid products often require a dry lawn for optimal absorption, and many become rainproof after an hour of drying. Always follow the specific instructions on your product’s label.
Q: Can I use a weed and feed product instead of a dedicated weed killer?
A: Weed and feed products offer the convenience of fertilizing your lawn while also killing common broadleaf weeds. They are excellent for general lawn maintenance and minor weed issues. However, for tough or widespread weed infestations, a dedicated post-emergent weed killer is usually more potent and effective.
Q: What should I do if the weed killer doesn’t work after one application?
A: If a product doesn’t work, first check if you identified the weed correctly and if the product is designed for it. Ensure you followed all application instructions regarding mixing, weather conditions, and timing. Some stubborn weeds may require a second application after a specified waiting period, which is typically outlined on the product label.
As an Amazon Associate, We earn from qualifying purchases