Bermuda grass can be yellowed, stopped, and even killed by the correct application of Atrazine herbicide. Atrazine kills actively growing Bermuda grass and kills Bermuda seeds as they sprout, making it an effective post-emergent and pre-emergent Bermuda killer.
For best success using Atrazine to kill Bermuda grass, follow these guidelines:
- Apply Atrazine only in St. Augustine, Centipede Grass, or Zoysia yards. It will harm all other grasses.
- Atrazine is most effective at killing Bermuda grass when it is applied in spring.
- Use a high-quality Atrazine-based weed killer and follow label directions to stop Bermuda grass and broadleaf weeds.
Make sure to apply Atrazine only to lawns that are Atrazine friendly. Also, do not spray garden plants with Atrazine, as it will kill most plant species.
Table of Contents
When Should You Spray Bermuda Grass with Atrazine?
Apply Atrazine to Bermuda Grass during spring green-up. At this point, Bermuda grass is actively growing but is not strongly established, so you have the best chance of killing it with Atrazine. Spring green-up is also the time when Bermuda seeds sprout. By spraying Atrazine, you will kill all seeds that attempt to sprout for up to 6 weeks.
Keep the following in mind when applying Atrazine:
- Spring is the best time to use Atrazine to kill Bermuda and stop new seeds from sprouting.
- A summer application of Atrazine will not be effective. Bermuda grass is too well established late in the year.
- Apply when daytime highs are 55–85℉. Cooler or warmer temperatures reduce effectiveness.
- Do not spray dormant Bermuda with Atrazine. Atrazine is ineffective at killing dormant grass.
- Do not spray Atrazine if you have overseeded your lawn in the past 4 weeks or plan to overseed within the next 6 weeks.
Atrazine is unique among herbicides because, when mixed with the right amount of water, it kills Bermuda grass and stops seeds from sprouting. However, it may stop all seeds from sprouting for up to 6 weeks. The good news is, this is not a worry for St. Augustine grass yards, since St. Augustine spreads primarily through stolons (runners), not seeds.
What Grass is Safe for Atrazine?
Only two common turfgrass species are NOT harmed by Atrazine. These are:
- St. Augustine
- Centipede Grass
All other turfgrasses that may be invaded by Bermuda, including Zoysia and Buffalo grass, will be harmed by Atrazine. If your yard has any grass other than St. Augustine or Centipede Grass, do not apply Atrazine.
Atrazine is a weed control measure that is effective against both broadleaf weeds and grassy weeds. By applying it to the right yard, you will stop Bermuda grass along with other weeds.
What is the Best Spray to Kill Bermuda Grass?
Use a specially formulated spray for St. Augustine and Centipede grass yards that contains Atrazine. Spectracide Weed Stop contains Atrazine combined with surfactants. This causes the herbicide to adhere to Bermuda grass and other weeds and kill the unwanted plants.
Spectracide Weed Stop is a terrific one-stop product for weed control and killing Bermuda grass. It’s one of the best herbicidal products for St. Augustine and Centipede Grass lawns because it kills so many pest plants and leaves your turf grass unharmed.
How Long does Atrazine Take to Kill Bermuda Grass?
Allow 4–6 weeks after Atrazine application to see full results. It is a slow-acting herbicide that needs time to break down plant systems. Signs that Atrazine is working are:
- Bermuda leaf blades begin to turn yellow at the edges.
- Fewer Bermuda runners from existing Bermuda patches.
- Little to no new Bermuda sprouts.
Allow time for Atrazine to work. Results will not be immediate, but Atrazine will begin to break down Bermuda grass at the same time it is at work below the soil surface, killing Bermuda seeds that attempt to germinate.
What is the Best Bermuda Grass Killer?
Atrazine is great at halting the spread of Bermuda grass and, if used correctly, can be effective at killing existing Bermuda grass. However, Bermuda is very tough to wipe out. If Atrazine isn’t getting the job done on its own, there are other options to kill Bermuda grass.
- Roundup or other Glyphosate-based weed killers can be used to spot-treat Bermuda.
- Ornamec 170 is an especially effective Bermuda Grass killer that is safe for use in most lawns.
Keep in mind when using Roundup or a similar product that glyphosate is a non-selective herbicide. This means it will kill any plant it is sprayed on, including your desired turf grasses. If you can’t isolate and spray Bermuda grass without affecting other grasses, use Atrazine or Ornamec 170.
How Long does Atrazine Last on Bermuda Grass?
Atrazine remains active for up to 6 weeks. During this time frame, it does 2 things:
- Kills established Bermuda grass and other weeds above ground for up to 6 weeks.
- Remains in the soil for up to 6 weeks, killing seeds as they sprout.
It’s essential to keep both these factors in mind. Not only is Atrazine harmful to plants for up to 6 weeks after application, it also works as a pre-emergent weed killer. This means that any grass or other plant seeds will be killed as soon as they begin to sprout. Wait 6 weeks after application before you seed grass or other plant seeds in an area that has been sprayed with Atrazine.
Atrazine is safe for humans and animals. Simply allow the Atrazine to dry after application and your yard is ready for use by pets and children.
Atrazine as a Bermuda Grass Killer
Atrazine is a selective herbicide for weed control in St. Augustine and Centipede grass yards. It will effectively halt and/or kill invasive Bermuda in lawns because it works both as a pre-emergent and postemergence herbicide. This means it kills the Bermuda grass you see and kills Bermuda seeds below ground as they germinate.
For best results killing Bermuda grass, spray Atrazine in spring, when daytime temperatures are 55–85℉ and your lawn is just beginning to exit dormancy. If applied in the height of summer, Atrazine may not be effective at killing Bermuda grass, and a winter application will not harm dormant Bermuda.
By applying in spring you will kill the most Bermuda, stop new sprouts, and get great weed control in your St. Augustine or Centipede lawn.