Post Emergent Herbicides: Selective vs Non-Selective
by:
GreenGate Turf, Pest, & Irrigation
Weeds are one of the most common challenges homeowners face when trying to maintain a healthy lawn. Even well-maintained lawns can develop weed problems during the growing season. When weeds begin appearing in your yard, post emergent herbicides are one of the most effective tools available for controlling them.
Unlike preventative treatments that stop weeds before they germinate, post emergent herbicides are designed to target weeds that are already visible and actively growing. These products can quickly reduce weed pressure and help restore the appearance and health of your lawn.
However, not all herbicides work the same way. Understanding the difference between a selective vs non selective herbicide is important when determining which treatment is appropriate for your lawn. Each type has a specific purpose and is used in different situations.
In this guide, we’ll explain how post emergent herbicides work, the difference between a selective herbicide and a non selective herbicide, and when each should be used.
Post emergent herbicides are weed control products designed to eliminate weeds after they have already emerged from the soil and begun growing. These herbicides are applied directly to the visible weed and are absorbed through the plant’s leaves.
Once absorbed, the herbicide moves through the weed and interferes with important biological processes such as growth, nutrient absorption, or photosynthesis. Over time, the weed weakens and eventually dies.
A post emergent weed killer can be used to control many common lawn weeds that appear throughout the year. While pre-emergent treatments focus on preventing weeds from germinating, post emergent herbicides address weeds that have already broken through the soil surface.
For example, if crabgrass appears after the growing season has started, a crabgrass post emergent herbicide may be used to target the plant and stop it from spreading further.
Post-emergent weed control plays an important role in maintaining a clean and healthy lawn, especially when weeds develop in areas where preventative treatments may have worn off or been disrupted.
What Is a Selective Herbicide?
A selective herbicide is designed to kill certain types of weeds while leaving desirable plants, such as turfgrass, unharmed. This is why selective herbicides for lawns are widely used in professional lawn care programs.
Many common lawn weeds are broadleaf plants, which are biologically different from grasses like St. Augustine, Bermuda, or Zoysia. A selective herbicide takes advantage of those differences to target weeds without damaging the surrounding grass.
Selective herbicides for lawns are commonly used to control weeds such as:
Because a selective herbicide focuses on specific plant types, it allows homeowners and lawn care professionals to remove weeds while preserving the lawn itself.
Using selective herbicides for lawns helps maintain a thick, healthy turf that can better compete with weeds over time. When combined with proper mowing, watering, and fertilization, these treatments help reduce future weed problems as well.
What Is a Non Selective Herbicide?
A non selective herbicide works very differently from a selective herbicide. Rather than targeting specific weeds, a non selective herbicide kills nearly all vegetation it comes into contact with.
This includes weeds, grass, and other plants.
Because of this broad action, non selective herbicides for lawn areas must be used carefully. These products are not typically applied directly to healthy turf unless the goal is to remove all vegetation.
Instead, non selective herbicides for lawn maintenance are often used in locations where plant growth is unwanted or needs to be cleared completely.
Common uses include:
Clearing weeds from driveways and sidewalk
Controlling weeds along fence lines
Preparing areas for new landscaping
Removing vegetation before lawn renovation
A non selective herbicide can be very effective for eliminating large areas of unwanted plant growth. However, it must be applied precisely to avoid damaging desirable plants or turfgrass nearby.
Selective vs Non Selective Herbicide: What’s the Difference?
Understanding selective vs non selective herbicide products helps ensure that the right treatment is used for each situation.
A selective herbicide targets specific types of weeds while leaving desirable turfgrass intact. This makes it ideal for routine lawn weed control where the goal is to remove weeds without harming the grass.
On the other hand, a non selective herbicide eliminates most vegetation it touches. This makes it useful in areas where complete plant removal is necessary.
When comparing selective and non selective herbicide options, the primary difference comes down to the intended outcome. If you want to preserve the lawn while eliminating weeds, selective herbicides for lawns are typically the best solution. If the goal is to completely clear vegetation, a non selective herbicide may be the appropriate choice.
Using the wrong product can damage healthy turf or fail to address the weed problem effectively, which is why proper identification and application are important.
Using a Crabgrass Post Emergent Herbicide
Crabgrass is one of the most persistent weeds found in residential lawns. It thrives in warm weather and can spread quickly if left untreated.
While pre-emergent herbicides are usually the best defense against crabgrass, there are situations where crabgrass still appears during the season. In these cases, a crabgrass post emergent herbicide can help control the problem.
A crabgrass post emergent herbicide works best when the crabgrass plants are still young and actively growing. Younger plants are easier to control, while mature crabgrass can be more difficult to eliminate.
Because crabgrass can blend in with the surrounding lawn early on, it often goes unnoticed until it has already spread. Monitoring the lawn regularly allows treatments to be applied before the problem becomes more severe.
Why Professional Weed Control Makes a Difference
Although many weed control products are available to homeowners, choosing between a selective herbicide and a non selective herbicide requires a clear understanding of the lawn and the weeds present.
Professional lawn care providers evaluate the lawn to determine the types of weeds present and decide whether selective and non selective herbicide treatments are appropriate. They also understand proper application rates and timing, which are critical for achieving effective results without damaging the lawn.
Many professional programs also combine pre-emergent treatments with post emergent herbicides to provide year-round protection against weeds.
This comprehensive approach helps maintain a healthier lawn that naturally resists weed growth over time.
Professional Lawn Weed Control with GreenGate Turf & Pest
At GreenGate Turf & Pest, we understand how frustrating weeds can be for homeowners. Our lawn care programs are designed to address weed problems using carefully selected post emergent herbicides and other proven lawn care practices.
Whenever possible, we rely on selective herbicides for lawns that target weeds while protecting your turfgrass. This allows us to control unwanted plants without damaging the lawn you’ve worked hard to maintain.
In situations where complete vegetation removal is necessary, we may recommend the use of a non selective herbicide in specific areas such as hardscapes or renovation sites.
By combining professional expertise with targeted treatments, our team helps homeowners maintain healthier lawns with fewer weeds throughout the growing season.
Get Help Controlling Lawn Weeds
Weeds can quickly take over a lawn if they are not addressed properly. Post emergent herbicides play an important role in controlling existing weeds, but choosing between a selective vs non selective herbicide is key to protecting your lawn while eliminating unwanted plants.
If you’re dealing with persistent weeds or want help maintaining a healthier lawn, GreenGate Turf & Pest is here to help.
