The timing of pre- and post-emergent herbicide to your lawn is very important. Applying them too late or too early will basically be a waste of time, as well as wasting herbicide. So when to spray pre emergent herbicides?
How They Work
Pre emergent herbicides are an effective preventative for controlling weeds. Properly using a pre-emergent will establish a chemical barrier that will not kill established plants. The protective barrier breaks down in six to eight weeks. Use of a pre-emergent, therefore, requires proper timing to be effective – apply them very early in the spring season and once again in the fall season in preparation for the dormant winter weather. Read and follow the manufacturer’s instructions when using any pre emergent product.
The difference between a post-emergent herbicides is treating weeds that are established and growing. Contact weed killers are post emergent. Apply post-emergent later in the growing season, after weeds have been established and importantly before they have gone to seed.
Proper Lawn Care To Fight Weeds
Proper fertilization, mowing, irrigation and soil aerating are all important factors creating a dense lawn, however sometimes weather events are beyond your control. This can cause the lawn to thin out or become over watered. Applying a pre-emergent herbicide can serve as an insurance policy on the off chance the yard suddenly loses its luster.
You can choose many different types of post-emergent products kill already-growing weeds. Note that some selective post-emergent will not harm foliage other than the target weed. While non-selective will kill any plant it comes in contact with, including your grass. Please be refer to the product label for mowing restrictions prior to and after herbicide applications. Using a post emergent can be used as early as April in warm regions.
Pre-Emergent Herbicides Brands
- Oxadiazon is a great granular option – safe in all turf and ornamental grasses.
- Prodiamine is an economical and longest lasting due to lowest application rates.
- Surflan is a specialty herbicide used as a pre-emergent herbicide for the control of annual grasses and many broad-leaf weeds in landscapes
Post-Emergent Herbicides Brands
- Celsius Herbicide – Best for Warm-Season Grass Only (St. Augustine, Bermuda, Centipede, Zoysia)
- Speedzone Southern Broadleaf – Excellent control of Broadleaf weeds, safe in turfgrass.
Use With Caution
- Closely follow the herbicide manufacturer’s instructions. Failure to follow the manufacturer’s recommendations can increase the dangers associated with use of these chemicals.
- Always wear gloves and any safety gear specified by the herbicide manufacturer when applying these chemicals. Wash out all clothing after use.
- Be sure to use only the recommended amount of herbicide to prevent buildup in water tables that can harm the environment.
- After application, keep children and pets off a treated area according to the product instructions.
Store chemicals in a cool, dry and dark place safely out of children’s reach.