Ortho WeedClear Lawn Weed Killer (South), with its quick rainfast time and ability to eliminate weeds to the root, is the best weed killer for Arizona lawns. Sunday Dandelion Doom Herbicide and Spectracide Weed Stop For Lawns Plus Crabgrass Killer follow behind closely.
We did extensive research to come up with this ranking, considering factors like product efficacy, ingredients, and application method. We also included a buyer’s guide to help you choose the best weed killer for your Arizona lawn.
- 1. Ortho WeedClear Lawn Weed Killer (South)
- 2. Sunday Dandelion Doom
- 3. Spectracide Weed & Grass Killer 2
- 4. Ortho GroundClear Year Long Vegetation Killer
- 5. Spectracide Weed Stop For Lawns Plus Crabgrass Killer
- 6. Bonide Chickweed, Clover & Oxalis Weed Killer Concentrate
- 7. Natria Grass & Weed Control With Root Kill
- 8. Bonide Captain Jack’s Deadweed Brew
- 9. Compare-N-Save Weed & Grass Killer 41% Glyphosate
- 10. Ortho GroundClear Weed & Grass Killer 2
- 11. Green Gobbler 20% Vinegar Weed Killer
1. Ortho WeedClear Lawn Weed Killer (South)
Ortho WeedClear Lawn Weed Killer (South) is a lawn-safe weed killer that works against over 250 weeds, including clover, dandelions, chickweed, oxalis, and plantain. It kills weeds to the roots and shows visible results in a day, which, in our opinion, is quite long compared to other products on this list.
This weed killer becomes rainfast in an hour and is safe for most Arizona lawn grasses. If you have Zoysiagrass, wait until the grass enters its growing season because the active ingredients in this weed killer can sometimes stunt its growth when used during dormancy.
How to use: Ortho WeedClear Lawn Weed Killer (South) is ready to use and comes with a trigger sprayer, so all you have to do is spray on unwanted plants to get rid of them.
Specifications
Application type: Spray
Active ingredients: 2,4-D, 2-ethylhexyl ester; Mecoprop-p acid; Dicamba acid; Carfentrazone-ethyl
Selective: Yes
Rainfast: 1 hour
Visible results within: 24 hours
Systemic: Yes
OMRI certified: No
Available sizes: 24 fl oz, 32 fl oz, 1 gallon
Pros and cons
| What we liked | What we didn’t like |
| ✔ Ready-to-use and comes with a trigger sprayer ✔ Kills plants down to the roots ✔ Becomes rainfast in an hour ✔ Safe for common Arizona grasses ✔ Affordable | ✗ Takes 24 hours to show visible results ✗ Not eco-friendly |
Where to buy:
2. Sunday Dandelion Doom
This weed killer works against hundreds of weeds, including bluegrass, chickweed, crabgrass, groundsel, and dandelions. It kills these unwanted plants to the roots, so you don’t have to worry about them growing back for at least a year. Sunday Dandelion Doom herbicide shows visible results within an hour, which is among the best of all products on this list.
Sunday Dandelion Doom Herbicide becomes rainfast in three hours and is safe to use on all common turfgrasses in Arizona, including Kentucky bluegrass, fescues, centipedegrass, and Zoysiagrass. This weed killer is formulated with iron HEDTA, which makes the grass greener and suppresses lawn diseases like dollar spot, snow mold, and rust.
How to use: This weed killer is ready to use, so you can directly spray it on unwanted plants.
Specifications
Application type: Spray
Active ingredients: Iron HEDTA
Selective: Yes
Rainfast: 3 hours
Visible results within: 1 hour
Systemic: Yes
OMRI certified: No
Available sizes: 32 fl oz, 1 gallon
Pros and cons
| What we liked | What we didn’t like |
| ✔ Ready to use and comes with a trigger sprayer ✔ Kills plants down to the roots ✔ Becomes rainfast in three hours ✔ Results are visible in an hour ✔ Safe for common Arizona grasses ✔ Iron HEDTA makes the grass greener and suppresses lawn diseases ✔ Affordable | ✗ Not eco-friendly ✗ Bottle leaks sometimes |
Where to buy:
3. Spectracide Weed & Grass Killer 2
This weed killer kills any plant to the roots, including turfgrasses. Spectracide Weed & Grass Killer 2 is ideal for getting rid of unwanted plants on hardscapes, but be sure to cover desirable plants with plastic to protect them.
Spectracide Weed & Grass Killer 2 becomes rainfast in 15 minutes, which is the fastest among all products on this list, and starts working within three hours.
How to use: This product isn’t ready to use. Mix 24 fl oz of the concentrate with a gallon of water and transfer it to a trigger sprayer. This solution can treat approximately 300 square feet.
Specifications
Application type: Spray
Active ingredients: Diquat dibromide; Fluazifop-p-butyl; Dicamba, dimethylamine salt
Selective: No
Rainfast: 15 minutes
Visible results within: 3 hours
Systemic: Yes
OMRI certified: No
Available sizes: 16 fl oz, 32 fl oz, 64 fl oz, 1 gallon
Pros and cons
| What we liked | What we didn’t like |
| ✔ Kills plants down to the roots ✔ Becomes rainfast in 15 minutes ✔ Results are visible in three hours ✔ Affordable | ✗ Not safe for grass ✗ Difficult to apply compared to ready-to-use products ✗ Not eco-friendly |
Where to buy:
4. Ortho GroundClear Year Long Vegetation Killer
Ortho GroundClear Year Long Vegetation Killer kills both weeds and grasses, so it isn’t the right product for your lawn. However, if you want to get rid of unwanted plants from your driveway or walkway, this weed killer is an excellent choice. It starts working within an hour.
Apply when the temperature is over 60 degrees Fahrenheit because the warmer the weather, the quicker the weed killer will be absorbed. Cover desirable plants with plastic to protect them and spray on a windless day. If you accidentally spray the plants, wash them immediately. Ortho GroundClear Year Long Vegetation Killer becomes rainfast in an hour.
How to use: Ortho GroundClear Year Long Vegetation Killer comes in a concentrated form. Prepare a solution by mixing 24 fl oz of the concentrate with a gallon of water and transfer it to a trigger sprayer. This solution can treat up to 300 square feet.
Specifications
Application type: Spray
Active ingredients: Imazapyr, isopropylamine salt; Pelargonic acid and related fatty acids
Selective: No
Rainfast: 1 hour
Visible results within: 1 hour
Systemic: Yes
OMRI certified: No
Available sizes: 32 fl oz, 1 gallon, 2 gallons
Pros and cons
| What we liked | What we didn’t like |
| ✔ Kills plants down to the roots ✔ Becomes rainfast in three hours ✔ Results are visible in an hour ✔ Affordable | ✗ Not safe for grass ✗ Difficult to apply compared to ready-to-use products ✗ Not eco-friendly |
Where to buy:
5. Spectracide Weed Stop For Lawns Plus Crabgrass Killer
Spectracide Weed Stop For Lawns Plus Crabgrass Killer works against over 470 weeds like dandelions, chickweed, clover, and yellow nutsedge. It eliminates unwanted plants down to the roots and shows visible results in three hours, which is among the fastest on this list.
This weed killer becomes rainfast within three hours and is safe to use on all common Arizona warm- and cool-season grasses.
How to use: Spectracide Weed Stop For Lawns Plus Crabgrass Killer is a concentrate. Prepare a solution by mixing 24 fl oz of the concentrate with a gallon of water and transfer it to a trigger sprayer to treat up to 300 square feet.
Specifications
Application type: Spray
Active ingredients: 2,4-D, dimethylamine salt; Quinclorac; Dicamba, dimethylamine salt; Sulfentrazone
Selective: Yes
Rainfast: 3 hours
Visible results within: 3 hours
Systemic: Yes
OMRI certified: No
Available sizes: 32 fl oz, 1 gallon
Pros and cons
| What we liked | What we didn’t like |
| ✔ Ready to use and comes with a trigger sprayer ✔ Kills plants down to the roots ✔ Becomes rainfast in three hours ✔ Results are visible in three hours ✔ Safe for common Arizona grasses ✔ Affordable | ✗ Not eco-friendly |
Where to buy:
6. Bonide Chickweed, Clover & Oxalis Weed Killer Concentrate
Bonide Chickweed, Clover & Oxalis Weed Killer Concentrate can eliminate more than 100 difficult-to-control weeds down to the roots, including chickweed, clover, and dandelions. It becomes rainfast in an hour but can take up to a day to show visible results.
This weed killer is safe to use on all common Arizona grasses, including fescues, Kentucky bluegrass, Bermudagrass, and Zoysiagrass.
How to use: Bonide Chickweed, Clover & Oxalis Weed Killer Concentrate comes in a concentrated form. Mix 24 fl oz of concentrate with a gallon of water and transfer to a trigger sprayer. This solution can treat up to 300 square feet.
Specifications
Application type: Spray
Active ingredients: MCPA; Triclopyr; Dicamba
Selective: Yes
Rainfast: 1 hour
Visible results within: 24 hours
Systemic: Yes
OMRI certified: No
Available sizes: 16 fl oz, 1 gallon
Pros and cons
| What we liked | What we didn’t like |
| ✔ Kills plants down to the roots ✔ Becomes rainfast in an hour ✔ Safe for common Arizona grasses | ✗ Takes 24 hours to show visible results ✗ Not eco-friendly ✗ Difficult to apply compared to ready-to-use products ✗ Relatively expensive |
Where to buy:
7. Natria Grass & Weed Control With Root Kill
Natria Grass & Weed Control With Root Kill is an eco-friendly weed killer perfect for driveways and sidewalks, eliminating weeds down to the roots within a day. However, it isn’t ideal for lawns.
The warmer the weather, the quicker the weed killer will be absorbed, so apply when the temperature is over 60 degrees Fahrenheit. Cover desirable plants with plastic when applying. If you accidentally spray the plants, wash them immediately. Natria Grass & Weed Control With Root Kill becomes rainfast in an hour.
How to use: This product comes in a concentrated form. To make it usable, prepare a solution by mixing 24 fl oz of the concentrate with a gallon of water and transfer it to a trigger sprayer.
Specifications
Application type: Spray
Active ingredients: Ammoniated soap of fatty acids; Maleic hydrazide
Selective: No
Rainfast: 3 hours
Visible results within: 24 hours
Systemic: Yes
OMRI certified: Yes
Available sizes: 24 fl oz, 32 fl oz, 1 gallon, 1.3 gallons
Pros and cons
| What we liked | What we didn’t like |
| ✔ Kills plants down to the roots ✔ Becomes rainfast in three hours ✔ Eco-friendly | ✗ Not safe for grass ✗ Takes 24 hours to show visible results ✗ Difficult to apply compared to ready-to-use products ✗ Relatively expensive |
Where to buy:
8. Bonide Captain Jack’s Deadweed Brew
Bonide Captain Jack’s Deadweed Brew contains caprylic and capric acids that kill several weeds down to the roots, including black medic, chickweed, and dandelions. However, it also eliminates turfgrasses, so use this product only on hardscapes.
This natural weed killer becomes rainfast in three hours and starts working within five hours. Spray on a windless day and cover desirable plants with plastic when applying. If you accidentally spray the plants, wash them immediately.
How to use: Bonide Captain Jack’s Deadweed Brew is a concentrate. Mix 24 fl oz of the product with a gallon of water in a trigger sprayer to treat approximately 300 square feet.
Specifications
Application type: Spray
Active ingredients: Caprylic acid; Capric acid
Selective: No
Rainfast: 3 hours
Visible results within: 5 hours
Systemic: Yes
OMRI certified: Yes
Available sizes: 32 fl oz, 1 gallon
Pros and cons
| What we liked | What we didn’t like |
| ✔ Kills plants down to the roots ✔ Becomes rainfast in three hours ✔ Results are visible in five hours ✔ Eco-friendly | ✗ Not safe for grass ✗ Difficult to apply compared to ready-to-use products ✗ Relatively expensive |
Where to buy:
9. Compare-N-Save Weed & Grass Killer 41% Glyphosate
This weed killer eliminates all plants down to the roots, including turfgrasses. We recommend using this product on hardscapes where you don’t want plant growth for at least a year. The glyphosate ingredient in this weed killer also kills desirable plants, so don’t use it on your lawn.
Compare-N-Save Weed & Grass Killer 41% Glyphosate becomes rainfast in two hours and shows visible results in 48 hours. If there are desirable plants nearby, cover them with a plastic cover.
How to use: This weed killer comes in a concentrated form. Mix 24 fl oz of the concentrate with a gallon of water and transfer it to a trigger sprayer. This solution can treat up to 300 square feet.
Specifications
Application type: Spray
Active ingredients: Glyphosate, isopropylamine salt
Selective: No
Rainfast: 2 hours
Visible results within: 48 hours
Systemic: Yes
OMRI certified: No
Available sizes: 16 fl oz, 32 fl oz, 1 gallon, 2.5 gallons
Pros and cons
| What we liked | What we didn’t like |
| ✔ Kills plants down to the roots ✔ Becomes rainfast in two hours ✔ Affordable | ✗ Not safe for grass ✗ Takes 48 hours to show visible results ✗ Difficult to apply compared to ready-to-use products ✗ Not eco-friendly |
Where to buy:
10. Ortho GroundClear Weed & Grass Killer 2
Ortho GroundClear Weed & Grass Killer 2 kills weeds down to the roots. However, avoid spraying it on unwanted plants in your lawn because it’ll also kill turfgrass.
This weed killer becomes rainfast in two hours and shows visible results within 15 minutes, which is the fastest among all products on this list. Spray on a windless day and cover desirable vegetation with plastic when applying.
How to use: Ortho GroundClear Weed & Grass Killer 2 comes in a concentrated form. Add 24 fl oz of the concentrate to a gallon of water and transfer it to a trigger sprayer to treat approximately 300 square feet.
Specifications
Application type: Spray
Active ingredients: Ammonium nonanoate
Selective: No
Rainfast: 2 hours
Visible results within: 15 minutes
Systemic: No
OMRI certified: Yes
Available sizes: 24 fl oz, 32 fl oz, 1 gallon
Pros and cons
| What we liked | What we didn’t like |
| ✔ Kills plants down to the roots ✔ Becomes rainfast in two hours ✔ Results are visible in 15 minutes ✔ Eco-friendly | ✗ Not safe for grass ✗ Difficult to apply compared to ready-to-use products ✗ Relatively expensive |
Where to buy:
11. Green Gobbler 20% Vinegar Weed Killer
This eco-friendly weed killer eliminates both weeds and grasses, so it isn’t ideal for killing weeds on your lawn. However, it’s an excellent choice if you want to get rid of unwanted plants from your hardscape.
Green Gobbler 20% Vinegar Weed Killer becomes rainfast in three hours and shows visible results within a day. Spray when the temperature is over 60 degrees Fahrenheit because the warmer the weather, the quicker the weed killer will be absorbed. Cover desirable plants with plastic to protect them.
How to use: Green Gobbler 20% Vinegar Weed Killer is ready to use, so you can spray it directly on unwanted plants.
Specifications
Application type: Spray
Active ingredients: Glyphosate
Selective: No
Rainfast: 3 hours
Visible results within: 24 hours
Systemic: No
OMRI certified: Yes
Available sizes: 32 fl oz, 1 gallon, 5 gallons
Pros and cons
| What we liked | What we didn’t like |
| ✔ Ready to use and comes with a trigger sprayer ✔ Becomes rainfast in three hours ✔ Eco-friendly ✔ Affordable | ✗ Not safe for grass ✗ Takes 24 hours to show visible results |
Where to buy:
Buyer’s guide to weed killers
With so many weed killers on the market, choosing the right one for your lawn is crucial. Here’s all you need to consider when shopping for a weed killer:
Systemic vs. non-systemic
Many weed killers are systemic (kill weeds down to the roots), but some are not. Non-systemic weed killers only eliminate the part of the plant they are sprayed on, so you should dig and remove the roots to prevent regrowth.
Even if you’re using a systemic weed killer, you should remove the dead weeds to get rid of the eyesore, but you don’t have to worry about removing the roots.
Rainfastness
Weed killers work only if they sit for a while on the target weeds. While you can adjust your watering schedule, you can’t stop the rain. If you live in a rainy area, choose a weed killer that becomes rainproof quickly. Many weed killers on this list become rainfast within an hour, but some can take up to four hours.
Selective vs. non-selective
Weed killers target weeds and grass or only weeds, depending on the formula. Selective weed killers target only weeds, not grass, making them ideal for removing unwanted plants from your lawn.
Non-selective weed killers kill any plant they touch, including turfgrasses. These weed killers are ideal for driveways and sidewalks where any green is unwelcome. You can also use them to clear your lawn for reseeding. Here’s a guide on reseeding your lawn.
Cover desirable plants with plastic when using non-selective killers to protect them. If you accidentally spray the plants, wash them immediately.
Speed
Weed killers work at different rates. Some show visible results within an hour, while others can take a few hours or even days. Choose a herbicide that works at the speed you expect.
Eco-friendliness
Most weed killers are made of harmful chemicals to remove unwanted plants down to the roots. If you want an eco-friendly option, choose OMRI-certified herbicides, but they usually aren’t as effective.
Ease of use
Herbicides come in either ready-to-use or concentrated forms. Ready-to-use weed killers usually come with a trigger sprayer, so all you have to do is spray them on unwanted plants. Concentrated weed killers need to be mixed with water before applying.
Ready-to-use weed killers are ideal for spot-treating weeds, while concentrated ones work better in removing unwanted plants from larger areas.
FAQs
What are the most invasive weeds in Arizona?
- Johnsongrass (Sorghum halepense)
- Cheatgrass (Bromus tectorum)
- Puncturevine (Tribulus terrestris)
- Bull thistle (Cirsium vulgare)
- Field bindweed (Convolvulus arvensis)
Check out our guide on controlling invasive Arizona weeds.
Can weed killers prevent weeds from coming back?
Depending on the active ingredients, weed killers can prevent weed regrowth for a long time (up to a year) but not permanently.
What are the best weed killers to use on flower beds?
Here are some of the best weed killers for flower beds:
- Preen Extended Control Weed Preventer
- Ortho GroundClear Super Weed & Grass Killer 1
- Avenger Weed Killer Concentrate
- Harris 20% Vinegar Weed Killer
- Natural Armor All-Natural Weed & Grass Killer
What’s the best time to water Arizona lawns?
The best time to water your Arizona lawn is between 5 a.m. and 9 a.m. to allow water to penetrate the soil and reach the roots before the afternoon sun. Avoid watering in the evening because the excess water on the grass invites pests and diseases. Here’s a guide on the recommended watering schedule for Arizona lawns.
What are the best grasses for Arizona?
The best grass for Arizona can vary depending on the region. Here are some of the best choices:
Warm-season grasses:
- Bermudagrass
- St. Augustinegrass
- Buffalograss
- Zoysiagrass
Cool-season grasses:
- Kentucky bluegrass
- perennial ryegrass
- Tall fescue
When to hire a professional
Weeds are inevitable no matter how well you take care of your lawn. What matters is treating them at the right time to prevent them from taking over your yard. A good weed killer can help with that.
Dealing with weeds is a pain. If you need help with weed removal or any lawn maintenance activities, get in touch with Lawn Love. We connect you with the best pros in your area who can help you with everything related to lawn care.
Lawn Love participates in the Amazon Services LLC Associates Program and other retailer affiliate programs. Lawn Love may earn revenue from products promoted in this article.
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