6 Best Weed Killers (2023 Guide)

In this buying guide, our team closely examines some of the best weed killers available today. We’ll take a closer look at lawn weed killers, non-specific herbicides, pre-emergent weed control, and even some pet-safe herbicides that work well in organic gardens.

Below, we’ll review our top picks, key features, benefits, and limitations to provide you with all you need to make an informed decision.

Top 6 Weed Killers

• Best Weed Killer Concentrate: Sunday Weed Warrior Herbicide Concentrate
• Best Non-Toxic Weed Killer: Green Gobbler Vinegar Weed & Grass Killer
• Best Weed Killer for Large Areas: RM43 43% Glyphosate Plus Weed Preventer
• Best Weed and Grass Killer: Spectracide Weed & Grass Killer
• Best Weed Killer for Lawns: Roundup All-in-One Weed Killer for Lawns
• Best Weed Killer for Flower Beds: Ortho GroundClear Weed & Grass Killer

Best Weed Killer Concentrate

Pros and Cons

✔ Features OMRI-listed herbicidal soap
✔ Yields visible results in as little as 20 minutes
✔ Works in flower beds, near patios, along sidewalks, in mulched areas, and more

✘ May require recurring applications in some cases
✘ Not for use on lawns

What Customers Are Saying

We reviewed dozens of customer comments for Weed Warrior. We learned that satisfied customers are particularly fond of Sunday herbicides for their non-toxic, natural, and organic-compatible formulas and report great success in non-selective weed control applications. However, our team also found reviews from a few customers who claimed that weeds grew back in place after some time had elapsed.

Best Non-Toxic Weed Killer

Pros and Cons

✔ Safe for use around pets
✔ Glyphosate-free vinegar formula is 4x stronger than table vinegar
✔ Doesn’t require dilution

✘ Not grass-safe
✘ Gives off a strong odor

What Customers Are Saying

According to our verified buyer research, customers who left positive reviews liked that this product was inexpensive and safe for families with children and pets. However, our team also found reviews from a minority of dissatisfied customers that said it left an unpleasant smell and caused damage to wood surfaces.

Best Weed Killer for Large Areas

Pros and Cons

✔ High concentration works as an effective pre-emergent herbicide
✔ Works well for targeted or generalized applications
✔ Single application stays effective for up to 1 year

✘ Application requires users to wear personal safety gear
✘ Eliminates desirable vegetation if not used precisely

What Customers Are Saying

Our verified-buyer evaluations showed us a majority of highly positive reviews, and many customers stated this weed killer worked well on large areas and was simple to use. However, we learned from a handful of dissatisfied customers who said it took too long to kick in or was as effective as cheaper, generic brands.

Best Weed and Grass Killer

Pros and Cons

✔ Yields visible results within 3 hours of application
✔ Becomes rainproof within 15 minutes of application
✔ Effective on driveways, fencing, flower beds, around shrubbery, and on sidewalks

✘ Requires manual dilution
✘ Herbicidal compounds can damage lawns

What Customers Are Saying

Our customer research revealed many happy customers who said this product was long-lasting, fast-working, and persistent with tough weeds. However, we encountered some critical other reviews in which customers claimed that it caused damage to lawns and that it didn’t work as advertised.

Best Weed Killer for Lawns

Pros and Cons

✔ Sold in concentrated and ready-to-spray formulas
✔ Becomes rainproof within 3 hours of application
✔ Targets weeds at the root

✘ Not safe for use around pets
✘ May require multiple applications in some cases

What Customers Are Saying

We discovered that buyers who liked this weed killer said that it was easy to spread and killed multiple types of plants with a minimal amount of spray. On the other hand, our research also revealed some negative reviews due to Roundup’s toxic ingredients.

Best Weed Killer for Flower Beds: Ortho GroundClear Weed & Grass Killer

Pros and Cons

✔ Becomes rainproof within 2 hours of application
✔ OMRI-listed as safe for organic gardens
✔ Works on hardscapes, landscape beds, and troubled vegetable gardens

✘ Eliminates all forms of vegetation exposed to it
✘ Significantly less effective when applied to wet vegetation

What Customers Are Saying

According to our research, satisfied customers said this weed killer worked quickly, didn’t kill wanted plants, and featured a simple-to-operate nozzle and wand. However, our research also revealed that a few buyers found heavy applications ineffective at eliminating weeds entirely.

Weed Killer Buying Guide

Not all weed killers work well for every surface or weed. Here are several factors to consider when determining which weed killer is best for your needs.

Types of Weed Control

Different types of weed killers are recommended for different types of plants and areas of application. Here are some common types of weed killers to look out for.

Contact Herbicides

This type of weed killer kills plants as soon as it makes contact with them. Contact weed killers don’t attack the root system. Instead, they weaken the plant after two or more applications. This type of weed killer is effective for annual weeds that consistently reappear.

Residual Herbicides

These weed killers poison the soil, killing all plants within the treated area. They can be long-lasting, so avoid using this type of weed killer in areas frequented by pets or containing edible plants.

Systemic Herbicides

Systemic weed killers are applied directly to the foliage of a plant. They take several weeks to start working, but they fight the plant’s internal root system. This type of weed killer is suitable for plants that are difficult to kill, such as dandelions and poison ivy.

Weed Emergence

Emergence refers to how far along the weed’s growth cycle that weed killer must be applied. Some weed killers are pre-emergent, meaning they should be applied to prevent weeds from growing.

Post-emergent weed killers are used for weeds that have already sprouted. They kill the plant while also ensuring it doesn’t grow back.

Selective and Non-Selective Weed Killers

If you’re using a weed killer on flower beds or gardens, using selective weed killers is critical, as they avoid beneficial plants and solely target weeds. Meanwhile, non-selective weed killers destroy all plants in the vicinity.

Common Weed Types

When it comes to weeds that can damage your lawn, some are particularly invasive and detrimental. Here are some of the most common weeds to look out for in your lawn: 

Crabgrass

Crabgrass is an annual grass weed that spreads rapidly, forming dense patches that can choke out desirable grass species. It thrives in bare or thin areas of the lawn and can quickly take over your lawn if you don’t actively control it.

For more tips on how to fully remove crabgrass, check out the video below.

Dandelion

Dandelions are perennial broadleaf weeds with a deep taproot that allows them to survive and reproduce in various conditions. Their bright yellow flowers give way to fluffy seed heads that can disperse seeds over large areas, making them difficult to eradicate.

Broadleaf Plantain

Broadleaf plantain is a perennial weed with large, oval-shaped leaves that form a rosette pattern close to the ground. These weeds can tolerate compacted soil and spread rapidly. Plantain weeds are highly adaptable and can be challenging to eliminate once they begin to spread.

Common Purslane

Purslane is an annual succulent weed that forms low-lying mats. It has thick, fleshy leaves and can produce an abundance of seeds. Purslane is known for its ability to tolerate dry conditions and can quickly invade garden beds.

Creeping Charlie

Also known as ground ivy, creeping Charlie is a perennial weed that spreads by creeping stems. It forms dense mats and can smother grass and other plants. Creeping Charlie has vigorous growth and resilience, making it particularly difficult to control. 

Canada Thistle

Canada thistle is a perennial weed with prickly leaves and pink or purple flowers. It spreads through an extensive root system and can quickly colonize large areas. 

Japanese Knotweed

Japanese knotweed is an extremely invasive perennial plant that can grow rapidly, reaching heights of several feet at full growth. Its extensive root system can damage structures and disrupt native plant communities. Eradicating Japanese knotweed typically requires professional assistance.

Weed Killer FAQ

How do weed killers work?

Generally, weed killers are herbicides that interfere with weed growth by either destroying their root formation or restricting the growth and development of their cells, causing them to eventually die.

Are weed killers dangerous around pets?

It depends on the weed killer. Some aren’t safe for households with pets, while others are safe once dry. The safest option is a weed killer with an organic formula.

For specific guidance on herbicides and active ingredients to look out for, visit the Environmental Protection Agency (EPA) website.

What does OMRI mean?

OMRI stands for the Organic Materials Review Institute, a non-profit organization that provides independent reviews of products for organic farming and processing. OMRI reviews the ingredients and manufacturing processes to ensure they meet organic standards, and organic certifiers use their evaluations to determine if products are allowed for use in organic production.

What are the best weed killers for organic gardens?

Organic gardeners may prefer natural weed killers that vinegar, citric acid, clove oil, and other organic garden-friendly ingredients instead of harsh, noxious chemicals.

However, it’s important to note that even natural weed killers can harm desirable plants if not used correctly and can be toxic if consumed, so always read and follow the instructions carefully.

What is Glyphosate?

According to the EPA, “glyphosate is a widely used herbicide that controls broadleaf weeds and grasses.” It was approved for use in the United States in 1974 and continues to undergo re-evaluation and review by the EPA every 15 years.

How long does it take for weed killers to work?

Typical weed killers will take anywhere from 2–6 to kill the root of a plant. Certain herbicides will produce faster results, but these herbicides kill the flowering part of the plant and not its root system.

Who This Weed Killer Guide Is For

Whether you’re a budding gardener, professional landscaper, or seasoned homeowner, an effective, safe weed killer can transform your outdoor space into an oasis.

How We Selected the Best Weed Killers

To provide our readers with the best weed killer recommendations possible, we rely on several key sources of information to help guide our selection process.

Initial Research: Our research process began by generating a list of weed killers with a significant number of verified-buyer reviews and an average customer review rating of 4–5 stars. We looked at positive and negative reviews alike, focusing on information from both satisfied and critical buyers. 

Expert Insights: Through our years of experience, we’ve learned that listening to what others have to say is critical to building accurate, well-rounded articles. To complement our in-house expertise, our team looked for information from trusted publications and subject matter experts. We also drew insights from reader contributions.

Final Product Selection: We then pared the list down further by comparing each weed killer’s pros, cons, and means of application, then eliminating formulas that posed major health and safety concerns. We did all of this to find the best-in-class options for various vegetation types and scenarios.

Why You Can Trust Us

This Old House has empowered homeowners and DIYers for more than four decades with top-notch home improvement advice in the form of television programs, print media, and digital content. 

Our small team focuses on creating in-depth product and service review content. To date, we’ve published countless reviews of garden, lawn, and outdoor products—from fertilizer and garden hoses to patio furniture and snow blowers.

Once we conclude our research, we craft a comprehensive, user-friendly article of recommended products and additional information to help our readers make the best purchase.

Questions or Comments?

To share feedback or ask a question about this article, send a note to our Reviews Team at reviews@thisoldhousereviews.com.