You need a post-emergent herbicide if weeds are already a blemish on your lawn, hardscape, or garden beds. We researched weed control products at some of the largest garden suppliers in the country: Home Depot, Lowe’s, Amazon, and Walmart. After extensive analysis, we found the best post-emergent herbicides. Our list includes various products that tackle America’s toughest weeds.
Our top picks
Top 4 selective post-emergent herbicides – Reviews
Selective herbicides are formulated to target specific weeds. This means they won’t be effective for all types of weeds, but it also means they won’t damage your grass or landscape plants.
1. Ortho Weed B Gon Plus Crabgrass Control – Best overall
The best selective post-emergent herbicide is Ortho Weed B Gon Plus Crabgrass Control. It contains three powerful herbicides that kill over 200 grassy and broadleaf weeds, including crabgrass, dandelions, poison ivy, and ragweed. It starts working in just a few hours and gets rid of most targeted weeds within two weeks.
Although it’s safe for many common turfgrasses, you shouldn’t use it on St. Augustinegrass, Bahiagrass, bentgrass, carpetgrass, centipedegrass, or seashore paspalum. Some resilient weeds may need spot treatment two weeks after the initial application.
Specifications
- Active ingredients: 2,4-D, Quinclorac, Dicamba
- Application: Sprayer
- Coverage: 5,000 sq. ft.
- Product size: 32 oz.
- Type: Liquid, systemic
- Use sites: Established lawns with Bermudagrass, Zoysiagrass, buffalograss, Kentucky bluegrass, ryegrass (perennial and annual), tall fescue, and fine fescue.
- Weeds treated: Over 200 grassy and broadleaf weeds, including clover, crabgrass, poison ivy, spurge, and ragweed
Pros and cons
| What we liked | What we didn’t like |
| ✓ Treats over 200 weeds ✓ Kills crabgrass ✓ Kills ragweed | ✗ Not safe for all grass types |
Where to buy
2. Southern Ag 2,4-D Amine – Safe for southern lawns
Many southern homeowners with St. Augustinegrass or centipedegrass have difficulty finding a herbicide that won’t harm their lawn. Southern Ag 2,4-D Amine effectively kills non-grassy broadleaf weeds and is safe on just about every turf type, including cool-season and warm-season varieties.
The concentrated formula also gives you a lot of bang for your buck. Mix just 2-3 tablespoons of the product with 3-5 gallons of water to treat 1,000 square feet.
Specifications
- Active ingredient: 2,4-D
- Application: Sprayer
- Coverage: 20,000 sq. ft.
- Product size: 32 oz.
- Type: Liquid, systemic
- Use sites: Lawns, pastures, golf courses, parks, cemeteries, and roadsides
- Weeds treated: Non-grassy broadleaf weeds, including chickweed, clover, dandelion, ground ivy, poison ivy, thistle, and wild onion
Pros and cons
| What we liked | What we didn’t like |
| ✓ Safe for most grass ✓ A lot of coverage per bottle ✓ Very effective against most non-grassy broadleaf weeds | ✗ Doesn’t work on grassy weeds |
Where to buy
3. Gordon’s SpeedZone Lawn Weed Killer – Fastest results for cool-season grass
If you want a fast-acting broadleaf weed killer that’s safe for cool-season grass, try Gordon’s SpeedZone Lawn Weed Killer. It contains a mixture of contact and systemic herbicides that show results in as little as 24 hours, and most targeted plants die within one to two weeks.
Although the product is best for established cool-season lawns, it’s also safe for Zoysia and Bermudagrass. And you can reseed your lawn just two weeks after herbicide application.
Specifications
- Active ingredients: 2,4-D, Mecoprop, Dicama, Carfentrazone-ethyl
- Application: Sprayer
- Coverage: 14,000 sq. ft.
- Product size: 20 oz.
- Type: Liquid, Contains systemic and contact herbicides
- Use sites: Cool-season grasses, including Kentucky bluegrass, perennial ryegrass, tall fescue, and colonial bentgrass, and warm-season grasses Zoysia and Bermudagrass
- Weeds treated: Over 75 broadleaf weeds, including clover, dandelions, garlic ground ivy, spurge, and wild violet
Pros and cons
| What we liked | What we didn’t like |
| ✓ Fast results ✓ Good for spot-treating the lawn ✓ Can reseed the lawn in just 2 weeks | ✗ Not safe for most warm-season grasses |
Where to buy
4. Sedgehammer Plus Turf Herbicide – Best for nutsedge
If you want to get rid of nutsedge or kyllinga, we highly suggest Sedgehammer Plus Turf Herbicide. It’s the best selective herbicide that’s safe on lawns while effectively killing sedges. The product is also safe for most trees, shrubs, and ornamentals.
To simplify things, the packet’s granules already contain a surfactant, so you just have to mix it with water. Within a couple of weeks, you’ll notice the nutsedge turning yellow or brown, and within four weeks of the initial application, the nutsedge is annihilated.
Specifications
- Active ingredient: Halosulfuron-methyl
- Application: Sprayer
- Coverage: 1,000 sq. ft.
- Product size: 13.5 grams
- Type: Liquid, systemic
- Use sites: Established lawns, trees, and ornamentals
- Weeds treated: Yellow nutsedge, purple nutsedge, kyllinga, some broadleaf weeds
Pros and cons
| What we liked | What we didn’t like |
| ✓ Kills nutsedge ✓ Kills kyllinga ✓ Easy to mix | ✗ Slow to show results |
Where to buy
Top 3 non-selective post-emergent herbicides – Reviews
Non-selective herbicides will kill any plant they touch – that includes grassy weeds, broadleaf weeds, and, unfortunately, your lawn. Be careful when applying non-selective herbicides and try to limit contact with plants you want to keep.
1. Spectracide Weed and Grass Killer – Best overall
Our favorite non-selective herbicide is Spectracide Weed and Grass Killer. It kills most weeds and grasses, making it excellent for treating hardscapes, driveways, and garden beds. You’ll start seeing results in as little as three hours and can replant new vegetation in just one day. Its application is super simple because it comes ready to use in a trigger spray bottle.
Specifications
- Active ingredient: Diquat Dibromide
- Application: Spray directly from the bottle
- Coverage: 5,400 sq. ft.
- Product size: 128 oz.
- Type: Liquid, systemic
- Use sites: Driveway, garden beds, patios
- Weeds treated: Kills most common weeds and grasses, including clover, crabgrass, poa annua, poison ivy, and turfgrass
Pros and cons
| What we liked | What we didn’t like |
| ✓ Rainproof ✓ No mixing ✓ No additional equipment | ✗ May need more than one application |
Where to buy
2. RM43 Total Vegetation Control – Best for large areas
If you have a large area to clear, we suggest RM43 Total Vegetation Control. It kills almost everything, including weeds, grass, vines, brush, and trees, plus it prevents regrowth for up to one year. It’s great for eliminating all vegetation in fields, gravel parking lots, and around barns and buildings.
After applying the product, keep children and pets out of the area for at least 2 hours. If it rains a lot after application, you may have to reapply in 4-6 weeks.
Specifications
- Active ingredients: Glyphosate, Imazapyr
- Application: Sprayer
- Coverage: 17,297 sq. ft.
- Product size: 2.5 gal.
- Type: Liquid, systemic
- Use sites: Fence rows, gravel paths, sidewalks, driveways, parking areas, around barns
- Weeds treated: Most vegetation, including weeds, grass, vines, brush, and trees
Pros and cons
| What we liked | What we didn’t like |
| ✓ Kills everything ✓ Treats large areas ✓ Prevents regrowth for up to 1 year | ✗ Can’t replant in the area for at least 1 year |
Where to buy
3. Sunday Weed Warrior Non-Selective Organic Herbicide – Best organic
If you’re looking for a natural weed killer, try Sunday Weed Warrior Non-Selective Organic Herbicide. It dehydrates and kills several types of weeds, algae, grasses, and moss. You’ll notice results in as little as 20 minutes, and it kills most vegetation within 24 hours.
Weed Warrior comes in a ready-to-use spray bottle and is perfect for killing vegetation in flower beds, sidewalks, and mulched areas.
Specifications
- Active ingredient: Ammoniated soap of fatty acids
- Application: Spray directly from the bottle
- Coverage: 50 sq. ft.
- Product size: 32 oz.
- Type: Liquid, contact
- Use sites: Flower beds, patios, walkways
- Weeds treated: Algae, grass, moss, and weeds including bluegrass, chickweed, corn spurry, crabgrass, dandelion, groundsel, lambsquarters, lichens, mustard, pigweed, plantain, redroot, round-leaved mallow, sheep sorrel, shepherd’s-purse, stinkweed, and thistle
Pros and cons
| What we liked | What we didn’t like |
| ✓ Eco-friendly ✓ Kills weeds, grass, algae, and moss ✓ Works quickly ✓ Easy to apply | ✗ Not a lot of coverage per bottle |
Where to buy
Buyer’s guide to post-emergent herbicides
When weeds start sprouting, it’s time to shop for post-emergent herbicides. When comparing products, please consider the following:
Types of herbicides
The types of post-emergent herbicides include:
- Liquid vs. granular: Liquid herbicides are easier to apply evenly, but granular herbicides require less preparation.
- Systemic vs. contact: Contact herbicides kill the parts of a weed that they touch, such as the leaves and stems, while systemic herbicides are absorbed into the plant and circulated through its vascular system, killing the entire weed, including the roots. Systemic post-emergent herbicides take longer to work than contact products, but they are more thorough. Contact herbicides work well for spot treatment, but a systemic approach is preferred when treating the entire lawn.
- Selective vs. non-selective: Selective herbicides target specific weeds, and non-selective herbicides kill all vegetation. You’ll want selective products for your lawn so the grass doesn’t die, but most homeowners prefer non-selective weed killers for patios and driveways.
- Chemical vs. organic: Chemical herbicides may have adverse environmental effects, and some chemicals are toxic. Organic post-emergent herbicides are better for the environment but are often less effective and more expensive.
Ingredients
The following chemicals are commonly found in post-emergent herbicides:
- 2,4-D amine salts is a selective herbicide that kills broadleaf weeds in lawns, edible gardens, farms, and aquatic locations. It typically takes one to two weeks to work.
- Bentazone is a selective herbicide that targets broadleaf and sedge weeds. It’s used on lawns and edible crops such as beans and corn and typically takes one to two weeks to work.
- Dicamba is a selective herbicide that kills annual and perennial broadleaf weeds and woody plants in turfgrass, crop fields, and pastures. Expect results in two to three weeks.
- Glyphosate is a non-selective herbicide. Depending on what you’re trying to kill, glyphosate can take a few days to two weeks to work. It’s more effective in killing annual grasses than glufosinate.
- Glufosinate is a non-selective contact herbicide that’s quicker to kill broadleaf weeds than glyphosate. Weeds typically die within a few days of application.
- Halosulfuron-methyl is a selective herbicide that works great for treating lawn weeds such as nutsedge. It takes three to four weeks to work.
- Imazapyr is a systemic non-selective herbicide. It dries quicker than glyphosate, so it’s often preferred in wet climates. After applying, plants gradually die within a few weeks to months.
- Monosodium Methanearsonate (MSMA) is an arsenic-based herbicide that kills grassy and broadleaf weeds. The EPA regulates its use to prevent the contamination of drinking water.
- Quinclorac is a selective herbicide that targets broadleaf and grassy weeds. It takes 10 to 14 days to kill crabgrass.
- Triclopyr is a systemic selective herbicide that targets broadleaf weeds and woody plants. It takes about two to three weeks to work and is often used on lawns, farms, and landscaping.
Common ingredients in organic post-emergent herbicides include:
- Ammonium nonanoate is a fatty acid found in several plants and animals. This non-selective contact herbicide works in as little as a few hours.
- Caprylic acid is a fatty acid found in palm oil, coconut oil, and milk. It works as a non-selective post-emergent herbicide that is particularly effective against small weeds. It starts working in as little as a few hours.
- Vinegar is a non-selective contact herbicide that takes a few hours to days to work.
You might opt for organic herbicides if you want your lawn and garden to be more eco-friendly or if you’re concerned about the safety of children or pets in your family since organic ingredients tend to be a lot less harmful than chemicals if accidentally ingested.
Grass type
Homeowners who want to control lawn weeds must choose a post-emergent weed killer that won’t harm their grass. Warm-season grasses such as St. Augustine and centipedegrass can be damaged by herbicides targeting grassy weeds. However, chemicals like 2,4-D amine salts and Quinclorac won’t harm warm-season lawns.
Most lawn weed herbicides are safe for most cool-season grasses, but always read the label to make sure. Bentgrass is especially vulnerable to herbicidal damage.
Cost
Expect post-emergent herbicide to cost $10 – $80 per container, and a typical container treats anywhere from 200 to 50,000 square feet.
FAQ about post-emergent herbicides
You must know how and when to apply post-emergent herbicides to rid your lawn of weeds. The best time to start using post-emergent products is in early spring when young weeds first appear. It’s best to wait until the soil temperature is above 55 degrees Fahrenheit for at least three days, but the daytime air temperature is still under 85 degrees.
You can use post-emergent herbicides until the end of summer as long as the daytime temperature is still under 85 degrees. Applying herbicide in the morning on dry days with little wind is best.
The best weed prevention is a healthy lawn. The following lawn care will help control weeds in your lawn:
● Aeration: Lawn aeration improves soil drainage so your grass gets more food, water, and oxygen.
● Dethatching: Dethatching your lawn in the fall improves soil drainage and grass health.
● Mowing: It’s important to mow your lawn the right way. Start by using one of the best lawn mowers.
● Fertilization: A well-nourished lawn stands strong against weeds, so follow our guide to lawn fertilization.
● Pre-emergent herbicides: The best pre-emergent herbicides include Quali-Pro Prodiamine 65 WDG, Scotts Turfbuilder Halts Crabgrass Preventer, and Espoma Organic Weed Preventer. Unlike post-emergents, pre-emergent herbicides prevent weeds from sprouting in the first place.
The best lawn fertilizers include Safer Brand Lawn Restore Natural Fertilizer and The Andersons PGF Complete Fertilizer with Humic DG.
If you’re looking to get rid of weeds in a flower bed, we recommend checking out our top picks for the best weed killers for flower beds. The list includes pre-emergent and post-emergent herbicides with organic and synthetic ingredients that we find work best for flower beds.
If you don’t find what you’re looking for there, you can also explore the best weed killers overall, which include products we suggest for use on lawns, gardens, hardscaping, and anywhere else in your landscape.
When to call a lawn care pro
Homeowners who are serious about their lawns know the best weed killer is an experienced lawn care pro. Local pros can identify and adequately treat lawn weeds without harming your grass. Best of all, routine maintenance will keep your lawn lush and prevent future weed germination. So, call your local lawn care pro today and say goodbye to unwanted weeds.
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