Does Atrazine Kill Grass?

Atrazine is a common broadleaf herbicide typically applied to crops and fields where broad-leafed weeds may be a problem. It is a pre-emergent herbicide which means it prevents the healthy and normal growth of many young plants. However, in addition to crops, some grass types are also immune to the devastating effects Atrazine can have on plant health.

Will Atrazine Kill Grass?

No, in most cases Atrazine will leave established grass alone and perfectly healthy. Atrazine is one of the most common herbicides used on golf courses. However, this does not apply to every “grass” type or every plant used as a typical lawn grass species. Timing is also critical to use Atrazine effectively and avoid any harm to your lawn. Below is a list of common grass types as well as how Atrazine will affect them, if at all.

How Atrazine Affects Different Grass Types

Atrazine can cause devastating effects to small plants and seeds of most broadleaf and grassy weeds. It is a very effective herbicide and one widely used in crop production. If you happen to get some on your lawn, you can see how your grass type might respond in the list below.

Does Atrazine Kill Bermuda Grass?

Yes, Atrazine can be devastating to a Bermuda grass lawn. Atrazine can kill Bermuda grass sprouts, stunt new growth, and kill seeds at any time of year. Atrazine can also prevent the emergence of returning growth of Bermudagrass if applied during the winter or early spring.

Does Atrazine Kill Crabgrass?

Atrazine is somewhat dangerous for crabgrass. While Atrazine will kill crabgrass seeds and new sprouts, it will not harm current crabgrass plants or stunt new growth no matter when it is applied.

Does Atrazine Kill St. Augustine Grass?

Atrazine is generally safe for use on St. Augustine grass at any time of the year. It is not known to harm the growth of St. Augustine sprouts or seeds. There are even specific formulations of Atrazine designed to support the health of St. Augustine lawns.

Does Atrazine Kill Bahia Grass?

Yes, Atrazine will kill Bahia grass but only when it is used as a pre-emergent herbicide. This means it must be sprayed before the Bahia grass greens up or emerges in the spring. Atrazine will kill Bahia grass seeds.

Does Atrazine Kill Centipede Grass?

Atrazine is safe for use as a pre-emergent and post-emergent herbicide on centipede lawns. Atrazine will not kill any part of the centipede grass plant or stunt its growth.

Does Atrazine Kill Zoysia Grass?

Atrazine will not outright kill Zoysia grass, but it will stunt its growth, prevent new growth, and delay “greening up” if used while Zoysia is dormant or just coming out of a dormant period. Atrazine is not labeled as safe for use on Zoysia for home use and comes with several warnings and restrictions when sold for professional use on Zoysia lawns.

Does Atrazine Kill Fescue?

Atrazine has a high kill rate when used on fescue. While it is not as deadly as glyphosate, it can still cause severe damage in nearly all cases when used as a post-emergent. Atrazine is recommended for the control of fescue grasses and will kill both plants and seeds if used as a pre-emergent.

How Does Atrazine Kill Grass and Weeds?

Atrazine disrupts the photosynthesis process in plants. This leads to quick starvation. It does not prevent seeds from germinating but instead causes the very small sprouts to expend extra energy with no way to recover. This kills the young plant very quickly.

How Do You Clean Up Atrazine on a Lawn?

If Atrazine has been used on your lawn or has been spilled on your lawn it is very difficult to get rid of and it will likely burn or kill any susceptible plants it comes into contact with. The best thing you can do is to dilute the area with water, at least 5 gallons per square foot, and allow it to rest. Once you know what the damage is, you can take steps to amend the soil and reseed after a few weeks.

Atrazine, once in the soil, takes between 30 to 285 days to fully decompose, depending on climate conditions. This may make it difficult to repair a brown, burnt, or bare spot caused by Atrazine for weeks to months.