BEST WEED KILLERS | NOVEMBER 2017
Finding the right weed killer starts with knowing what type of weeds you want to kill. This guide focuses on the types weed killers most often needed by a typical homeowner. An agricultural grade weed killer is included for those with extensive property or looking to kill trees and woody plants like blackberries. ReviewLab strives to research and recommend products that meet product claims and satisfy customers. Read more about our methodology.
Compare-N-Save Concentrate kills most if not all plants it comes into contact. It may take a few days to see results, but it works well in driveways, at the edges of concrete, and other areas where plants are not wanted.Read full review.
Ortho Weed B Gon works well on the weed types indicated on the bottle. It comes as a concentrate, extending its use. It may take multiple applications but results can be seen within a few days.Read full review.
Weed Killers BUYING GUIDE
The most important consideration for most homeowners is selectivity. Selective weed killers target a specific type or group of weeds such as broadleaf plants like dandelions or woody plants like blackberries. Selective weed killers can be used on weeds that pop up in the lawn without harming the grass. Non-selective weed killers kill any vegetation they touch—weed, grass, or tree. They can be used to target grass and weeds growing in the cracks of concrete, alongside driveways, or between paving stones. Non-selective weed killers should be used with caution as they can damage surrounding lawn and trees.
Pre-emergent weed killers are applied before germination, killing weeds before they begin to grow. Post-emergent weed killers are applied to the leaves of the plant and can be either systemic or contact. Systemic weed killers are absorbed into the plant attacking the roots, stems, and leaves. They are effective but slower acting so results may not be obvious for a few days or weeks. Contact weed killers are sprayed directly onto the leaves. Results can usually be seen within a few hours of application. Which type you’ll need will depend on the weeds you’re targeting and how pervasive they’ve become.
Persistence describes how long after application the weed killer stays active. Those that prevent regrowth are called persistent and should only be applied in areas where you know you don’t want plants to grow in the future. Non-persistent weed killers stay active for few weeks or months. They may need to be reapplied for the best results.
Identify Your Weeds
Before you can purchase the right weed killer, you have to know the weeds invading your property. Even a broad spectrum weed killer won’t kill all weed species. The more you know about the weeds in your area, the better you’ll be able to target them. It’s worth researching their growing season and when they germinate, especially if you want to use a pre-emergent weed killer.
Under $15 or less, you can get a pre-mixed formula in a spray bottle or a concentrate. This type of weed killer is good for spot treatments in small yards with a few pesky weeds. In the $20-$50 range, you’ll find weed killer concentrates, pre-mixed formulas, and granular variety weed killers. Concentrations will need to be mixed for correct application. Products with a higher concentration are usually more effective and can cover a larger area for the price. At $60 and up, you’ll find even higher concentrations that are targeted at tough to kill species. In this upper price range are agricultural and commercial grade formulas with more complex mixing instructions.
FULL product reviews
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Compare-N-Save Concentrate Grass and Weed Killer is a 41% concentration of glyphosate, making it a high concentration product. It is a non-selective, systemic weed killer that needs to be diluted correctly before use. Once sprayed, it travels through to the roots killing weeds in two to four days. It works well enough that special care must be taken to prevent drift because it can kill most plants. If you need a good weed and grass killer at a reasonable price, Compare-N-Save is effective and the concentration can be adjusted for difficult to kill weeds.
Why We Recommend It
- Effectiveness. Compare-N-Save works well on grass and weeds. As a systemic weed killer, results are not immediate but that doesn’t mean it’s not working. It should not be used as a spot treatment because it will kill surrounding plant life.
- Future Growth. Because this is a post-emergent weed killer, replanting can take place within a few days of treatment. This allows you to kill weeds without damaging the soil. It can be used in gardens but follow directions as to when it is safe to replant.
- High Concentration. The high concentration not only kills weeds but also is cost effective. One container can make eighty-five gallons of weed killer.
- Future Weed Growth. As a post-emergent weed killer, it will not prevent new weed growth.
Ortho Weed B Gon Chickweed, Clover and Oxalis Killer for Lawn Concentrate successfully targets the selected weeds while leaving grass alive. (Although, according to the instructions Bermuda grass may be affected.) Multiple applications can be used every five days for difficult weeds. If you’re looking for an inexpensive way to get rid of chickweed, clover, or oxalis, this product will do the job.
Why We Recommend It
- Effective. It kills the plants it claims to kill. When sprayed over an entire lawn, it will take care of weeds, leaving the grass behind to thrive.
- Kills to the Roots. This weed killer does more than shrivel leaves, it reaches down to the root. It may take some time to see results, but once it works its way into the plant, death soon follows.
- Concentrate. Because it’s a concentrate, it allows you to mix as much or as little as you need. It can be applied with a spray attachment or tank sprayer.
- Specific. It only kills the weeds specified. If you have a wider variety of weeds, this might not be the best weed killer for you.
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Best Weed Killer for Lawns
To kill weeds but protect surrounding grass and vegetation, a selective weed killer that targets a specific species or types of weeds is the best choice. These weed killers can be species specific, such as those targeting poison ivy or dandelions, or they can target several types of weeds such as bull thistle, Canadian thistle, and broadleaf. They kill weeds yet leave grass and desirable vegetation unharmed. If dandelions or other pesky weeds sprout up in random locations, this type of week killer will allow you to kill the pest and keep the grass.
Southern Ag 2, 4-D Amine Weed Killer Selective Broadleaf Weed Control kills weeds but not grass. Getting rid of weeds in your lawn leaves space for grass to grow strong and full. Dandelions, chickweed, and poison ivy are only a few of the broadleaf plants this weed killer effectively targets. If you’ve got hard to kill weeds taking over your lawn, this Southern Ag is a good choice for you.
Why We Recommend It
- Effectiveness. Kills broadleaf plants though some may require multiple treatments and varying concentrations to get the job done.
- Concentration. With 46% active herbicide, this is a high concentration product. That gives some flexibility in the strength of the dilution. It’s always best to follow mixing instructions, but if a higher concentration is needed this weed killer can be made more powerful tough to kill weeds.
- Protects Grass. It leaves grass behind to fill in where weeds used to grow. You’ll still need to be careful when spraying. If there is too much overlap it can damage grass.
- Chemical Smell. This product leaves behind a distinct chemical smell that goes away with time. The strength of the smell may vary according to the strength of the dilution.
Best Weed and Grass Killer
A weed and grass killer is considered a non-selective weed killer because it will kill most plants, weed, grass, bush, or tree. It works best when applied to plants growing through the cracks of driveways, sidewalks, and patios. This type of weed killer can also be used on lawns before replanting. Caution should be used as this type can kill a healthy lawn. This type of weed killer works best for those who need to kill all vegetation in a specific area.
Spectracide Weed & Grass Killer with Extended Control Concentrate is powerful enough that even a drop can leave brown spots on healthy plants. It kills a broad spectrum of weeds and grasses, making it ideal for areas with many weed species. When applying, watch out for overspray or drifting as it will kill flowers, fruits, vegetables, and grasses. For those who want a powerful formula for those hard to kill weeds and grasses, this is a good choice.
Why We Recommend It
- Effective. This contact weed killer begins to affect vegetation within a few hours. Results are easy to see, so you’ll know if you missed an area. It does not kill seeds so a second application may be necessary to kill new growth.
- Rain Fast Time. It becomes rain fast in just 15 minutes. This weed killer will work for those in heavy rainfall areas.
- Driveways and Sidewalks. Because it kills both weeds and grass effectively, it is ideal for use along driveways and sidewalks. It can eliminate plants that grow in cracks and damage concrete.
- Price Per Ounce. Spectracide takes a heavy concentration to kill weeds, making it less cost-effective than some other choices.
Best Non-Toxic Weed Killer
Growing concerns about the environmental impact of herbicides mean non-toxic weed killers are growing in popularity. Organic weed killers fall in this category though all non-toxic weed killers are not organic. This type of weed killer is most commonly used in a garden or other areas where food is grown. Families with small children or pets may want to consider going non-toxic to reduce the risk of exposure to harmful chemicals.
Avenger Organics Weed Killer Concentrate uses ingredients like oranges and citrus oil to attack weeds. It is nonselective, so it kills both weeds and grass, showing results within a few hours. Because of its organic formula, it doesn’t damage driveways or sidewalks when used to kill weeds alongside or growing in cracks. This weed killer works well for those with children, pets, or a garden as it safely kills weeds without harmful chemicals.
Why We Recommend It
- Environmental Safety. As an organic weed killer, it uses biodegradable ingredients that will not cause harm to the environment. Pets and children can play in an area that’s been sprayed with Avenger as long as it has dried. It also breaks down so as not to harm soil for future growth.
- Immediate Results. This product works quickly. It is a contact weed killer that is absorbed through the leaves. Depending on the strength of the dilution, results can be seen in as little as a few minutes up to a couple of hours.
- Use in the Garden. This weed killer allows you to control weeds in a garden without worrying about chemicals being absorbed into your food.
- Cost. The overall cost may be higher than some synthetic weed killers because a larger amount of weed killer is needed, especially with resilient weeds.
- Effectiveness. Avenger works well for an organic weed killer, but persistent and hard to kill species may not respond. Some will require multiple applications.
Best Weed and Feed
Weed and feed formulas are a weed killer/fertilizer combo. The weed killer chokes out weeds like dandelions while the fertilizer strengthens the remaining grass. As weeds are eliminated, it opens up space in the root system for grass to flourish. Weed and feed should be applied evenly to the entire lawn to stop weeds from spreading. Though this type of weed killer isn’t as effective at killing weeds as a non-combination formula, they work well for those who want to prevent weeds and maintain a healthy lawn.
Scotts Turf Builder Weed and Feed Fertilizer 5M is a fertilizer/weed killer combination. As it kills weeds, it feeds the lawn to help choke out further weed growth. It is most effective on dandelions and clover. Results can be seen after one use. Killing weeds may require more than one application. This weed and feed is good for those who are looking for an easy way to get rid of a few pesky weeds while fertilizing their lawn.
Why We Recommend It
- Fertilizer. The fertilizer works well to bring lawns back to life. In general, the fertilizing element of this formula works better than the weed killer. But as grass grows in thicker, it helps choke out future weeds.
- Dandelion and Clover. The weed killer is highly effective on dandelions and clover. Some weeds can be eliminated with just one use while larger infestations may require multiple applications.
- Ease of Use. There is no mixing or diluting of a concentration with this product. The bag can simply be opened and poured into a spreader for easy use.
- Drought Conditions. Be careful on grass that is dry or experiencing drought conditions as it can easily be burned by weed and feed.
- Weeds. As with most weed and feeds, it is not as effective as a weed killer. Weed and feed works best for those who have a small problem with dandelions and clover.
Best Agricultural-Grade Weed Killer
Agricultural-grade weed killers target the usual weed species but also kill trees, bushes, and other woody plants. Mixing instructions for this type of weed killer can be more complicated. Some, but not all, may require a mixture of oil as well as an emulsifier, such as soap, to create the correct solution. Once sprayed, the solution sticks to the leaves or stumps of the chosen plant. Those who have a continuing problem with highly invasive weeds, brush, or trees may find an agricultural-grade weed killer a good choice.
Agri Star Triclopyr 4E Herbicide is a powerful systemic weed killer that can kill trees as well as broadleaf plants like ivy and dandelions. This high concentration product must be mixed with a light oil and a small amount of dish soap to be most effective. The oil helps the solution stick to leaves while the soap allows the weed killer to mix with the oil. Because of its high concentration, Agri Star can cover an extensive amount of property. This kind of weed killer works best for those with a wide variety of hard to kill weeds and have a large area to spray.
Why We Recommend It
- Effectiveness. When mixed correctly, this weed killer does its job well. Woody plants and trees can be difficult to target, but Agri Star is strong enough to kill these hard to target plants. It’s effective enough that care should be taken when spraying as any drift onto desirable trees may result in damage or death.
- Concentration. At 61% concentration, one bottle will go a long way. It also allows for adjusting the dilution for tough to kill weeds.
- Kills the Whole Plant. As a systemic weed killer, it kills the entire plant not just the leaves.
- Complex Mixing Instructions. Poor mixing instructions on the container can be confusing. The mixing instructions are more complex than many concentrations so be sure to read directions completely before mixing.