When To Apply Weed Killers? (Updated on Dec 2023)

A vital task in effective weed killer lies in proper application over weeds; that’s where it matters. An appropriate application of weed killer seems to be a time and effort-saving solution to your lawn problem.

However, applying weed killer at the wrong time of the year, or on the wrong kind of lawn, can keep them from growing correctly.

Learn when to apply weed killers and choose an alternative to keep your grass green and your yard safe.


Some weed killers contain broadleaf herbicides intended to kill green plants and leave your grass.

Some products also contain pre-emergent herbicides that kill crabgrass and other grassy weeds.

Manufacturers combine these chemicals with fertilizers to provide nutrients for the growing lawn.

Weedkiller to work correctly, apply weed killer at the perfect time.


Crabgrass and related weeds are best killed using pre-emergent herbicides, which keep the weed from growing than post-emergent types, which kill on contact.

The weed killer sprayed before the weed started to emerge from the ground. At the same time, pre-emergent herbicide won’t work if the weed has its head.


Post-emergent herbicides kill broadleaf plants on contact but don’t usually adhere to grass blades. Applying too much of this kind of weedkiller may kill all of your grass.

So kindly use these types of products according to the manufacturer’s instructions when weeds have emerged.

You have to wait for some days after mowing to ensure profitable weed growth for the herbicide to work.


Apply weed killer to grass mowed at average height once or twice per year.

Strictly avoid using these products in drought because they are incompatible with uniformly over wet grass.

Don’t water the lawn for at least two days and avoid planting new grass or aerating the yard for four weeks.

Generally, the application of weed killer for all types we have given in nine easy step process; they are

  1. Early application of weed killers would be the best time; after it has grown stronger, it would be a little challenging task.
  2. Choose the best season and time for application.
  3. Don’t mow the lawn before or after weed killer application.
  4. Water the lawn lightly before application.
  5. Apply in the early morning.
  6. Avoid watering after treatment for two days.
  7. Stay off the yard for one day.
  8. Avoid pets in sprayed areas for one day.
  9. After crossing one day, wash out the weedkiller and use the lawn.

Before applying weed killer over your weeds, few questions you have to ask yourself the following questions given below,

1. what type of weed do we have?

2. did we want to control it before it germinates?

3. do we have annual or perennial weed?

4. when is a proper time to apply?

5. Goal to prevent weed or eradicate them, or both?

6. what are the life cycles of weeds? 

If you have an answer for all of these questions, then it’s a perfect time to apply your weedkiller over your weeds.

These questions must be asked to yourself to get the best result without collapsing.


Weedkiller contains chemicals that harm humans, wild plants, and animals.

To a report of Thurston county public health and social services and texas A&M university, these chemicals frequently get into groundwater.

They are tracked inside by humans and pets. These chemicals have been linked to cancer, neurological problem, and reproductive conditions.

Avoid weed killers if you have other alternatives.


It’s impossible to kill all weeds because each weed has a different survival strategy, different life cycles, and reproduction; thus, eliminating entirely is not possible.

Seeds may lay dormant for so many years under the ground before they germinate.

Even if you completely clear all weeds, a seed can easily be transported by water, animals, wind, or human activity.


Weeds don’t see season; they grow all year round. But you people doubt which season to apply to get the best result. Yea, I have an answer.

The best season to use is spring or fall. Simple logic lies that the spraying of weed killers must be stopped over the hot summer or freezing season.

During the hot season, the weedkiller evaporates, and while during the freezing season, the weedkiller gets frozen.

So it is advised to use only during moderate temperature; that’s why spring is the best season to use weedkillers.But most of them still doubt if weed arises during hot summer and what to do if you leave it for next season, it grows even more robust.

At that time, what to do?. I have a clear answer that weed killers are advised only not to use in the extremely hot, but it can be used in warm temperatures. For a safe application spray only eight weeks later. See the safety of the environment and all creatures around you and use it in a safe way.

Maurice Johnson

Maurice Johnson

I’m Maurice Johnson, and first of all, I’d like to welcome you to my website. Here at bestweedkiller.org, we keep it simple.

At bestweedkiller.org, you’ll find updated reviews and tests of the most popular brands of weed killers and other accessories.

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