How Soon After Spraying Weeds Can I Mow

Pulling weeds by hand can be a strenuous job that may take hours of your time on any given day. Using a concentrated weed killer can get the job done in a short amount of time and will keep weeds at bay for a longer duration. After adding weed killer, many people wonder how soon after spraying weeds they can mow.

Mowing your yard too soon after applying weed killer will render it unusable and not allow it to do its job completely. Waiting 24 to 48 hours to mow your yard ensures that the weed killer has time to do its job and allows you to not come into contact with it too early.

mowing grass

This article will explain the different types of herbicides and weed killers and what is recommended to get the job done right. We will also talk about how long to wait to water and how to keep your family and pets safe.

How Soon After Spraying Weeds Can I Mow

It is recommended to let the weed spray sit on your yard for at least 24 hours to let it absorb and allow you to mow successfully. If you try to mow too soon after applying you aren’t allowing the weed killer to do its job by sinking into the roots and leaves of the plant and killing it off.

Besides waiting to mow, you should also be aware of pets and small children around herbicides and weed killers. Both pets and children coming in contact with herbicide can be a major safety hazard. Allowing the herbicide to sit for a few days before people and pets come in contact with it is recommended.

In order to combat weeds in the future you can cut your yard only one third of the length each time. Cutting your yard too short in one go can cause your yard to become highly stressed and will quickly thin out. When your yard begins to thin out is when weeds have an optimal chance to thrive.

Should I Spray Weeds Before or After Mowing

Spectracide HG-96587 Lawn Weed Killer, 1 gal

In many people’s minds, mowing your yard before you apply weed killer means you are closer to the weeds surface which makes it more effective. The opposite is actually right for many weed killers. When it comes down to it, there are two types of weed killers that you can use in your yard, pre-emergent and post-emergent.

Post Emergent

Post Emergent weed killer is created to attack the part of the plant, such as the leaves, and then continue to be absorbed into the roots.

Mowing your yard before applying post-emergent herbicide will cut off parts of the weed, such as the leaves that typically help weed killer work faster. The leaves absorb the weed killer and transfer it into the roots, which eventually will kill the plant off. You want to have as much leaf as possible for post emergent weed killers to have a large enough surface area to work properly.

Mowing your yard regularly will help to keep it healthy through every season of the year and create a dense yard that should keep weeds away.

Pre Emergent

Pre-emergent herbicides get rid of weeds before they even germinate out of the soil. Mowing your yard before applying pre-emergent spray will allow the spray to be in better contact with the soil. You must also remember that pre-emergent weed killers must be activated by watering them, which may add more days till your yard is ready to be mowed.

No matter what weed killer you use, it is recommended to figure out what works best for the exact weeds you are trying to kill. Another aspect is that if your yard is insanely high, you may need to cut your yard slightly so the weed killer is effective.

Waiting to mow till at least two days after you apply herbicide will allow the weed killer to do its job and truly kill off the weeds correctly. You can wait to cut your grass for at least four days before applying weed killer and two days after.

How Long Should I Wait to Water After Spraying for Weeds

VIVOSUN 1.3 Gallon Lawn and Garden Pump Pressure Sprayer with 3 Water Nozzles, Pressure Relief Valve, Adjustable Shoulder Strap

Watering too soon after applying weed killer can ruin the effect it will have on the plants it is applied too. It can quickly wash away all of the hard work you put into applying weed killer plant by plant. Waiting a few days before watering makes sure that the weed killer has had a chance to absorb into the parts of plants it needs to in order to work properly.

It is recommended to wait at least a day for the weed killer to dry and work its magic on all of the weeds. Make sure you are always careful when watering because if you use water too soon or water too much you will lower how effective the weed killer is on your yard’s leaves.

How Long Does it Take for Weeds To Die Completely

After spraying weeds it usually takes one to two weeks for them to completely die back. Although you definitely do not have to wait that long to mow and water your grass, it is important to know to ensure your weed killer worked properly.

What Steps to Take to Ensure Weeds Don’t Grow Back

You have taken the time to spray weed killer on each weed you see, and you want to make sure that weeds stay away for good. There are several steps you can take to minimize the chances of weeds coming back again and again. 

Weed Killer is a good option if you have an overabundance of weeds that you need gone fast, but it is definitely not the best option for the environment. After all of the weeds die back you will need to go in and remove dead weeds and get rid of them so you don’t have piles of dead weeds laying around your yard.

A downside or negative side of weed killers is that if they are not sprayed the correct way you could risk not killing the entire plant and it coming back. Pulling weeds by hand is the best option for getting rid of the plant entirely, but weed killer is great start for an overgrown yard.


Weed killer is a great choice to get rid of a ton of weeds in a short amount of time. Taking the necessary steps to ensure it is effective and has time to kill the weed entirely is crucial. Homeowners wonder how soon after spraying weeds they can mow and the answer is 24 to 48 hours.

You need to always remember to give the weed killer a chance to absorb into the plant and kill it off rather than rushing it and risking having to apply weed killer again and again.

After applying weed killer you should also keep family and pets off of the treated yard and wait to water for a few days until the weed killer has absorbed completely. Once your weed killer is effective and kills off the weeds, you can go around and pick up the old weeds and dispose of them properly.

Spectracide HG-96587 Lawn Weed Killer, 1 gal

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