If weeds have overrun your lawn, you might want to think of an effective way to control them. While pulling them out by hand is an option, it’s not logical for a large lawn with many weeds. A good option is to spray the weeds first and then mow your lawn afterward. But how soon after spraying weeds can I mow?
Herbicides, like other chemicals, require a specific time frame in which they act on the weeds. After spraying, you should wait for at least two to three days before cutting your lawn.
Here’s a guide that will help you the next time you want to get rid of weeds from your lawn.
How Soon after Spraying Weeds Can I mow?
Yes. You should mow your lawn after spraying weeds. However, make sure to give the weed killer enough time to act on the weeds before you cut your grass.
Mowing after spraying weeds keeps your lawn tidy. It also allows you to remove the dead weeds, leaving your grass short and manicured. Cut your lawn grass at least two days after spraying the weeds.
Weed killers work by getting in contact with the weed’s leaves. For the chemical to be most effective against weeds, you need to spray it on a broadleaf surface. The more the leaf surface, the faster it will act on the weed.
This means that the best time to spray is before mowing your lawn, when the weeds are at their tallest. Whether you’re spot spraying the weeds or using granular weed killer, you want to have the weeds at their tallest. After you mow, the leaf surface reduces, and you might not get the results you desire.
You can find the short answer to this question on the packaging of the RoundUp weed killer you’re using.
Most herbicides have a recommended waiting period of two days before you can mow your lawn. However, remember that some herbicides may require several sprays at different intervals.
When using weed killer, you may have to spray at intervals of 2 weeks to kill any recurring weeds. Some weed killers work best under certain temperature conditions, so plan your spraying ahead of time when the weather meets these requirements.
After mowing your lawn, inspect it to see whether any weeds have popped back up. You might need to wait a few more days for the leaf surface of the weeds to increase before spot spraying them.
How long does it take to kill weeds after spraying?
When using weed killers, you will most likely find information on their strength and mowing schedules on the labels. Strong chemicals may take a few hours to completely kill the weed, while less concentrated ones may take up to a day or two.
More importantly, you need to let your lawn be for at least two days to give the weeds enough time to absorb the chemicals down to the roots.
Also read: What do I do with dead weeds after spraying?
Different weed killers work in various ways. The most conventional weed killers are:
- Systemic weed killers
- Contact weed killers
- Non-selective weed killers
- Residual weed killers
- Selective weed killers.
Systemic and contact killers are the most common among the conventional weed killers listed above.
If you stumbled upon this article after mowing your lawn, all hope is not lost. Here’s what you need to do.
Although it’s not conventional, some homeowners prefer mowing their lawn before spraying the weeds. However, this is only recommended if you have an already matured lawn. After about two days, most matured lawns recover from the stress caused by mowing. Only then can you spray the weeds on your lawn.
The downside to this method is that there isn’t much leaf surface to absorb the chemicals from the herbicide. So you might miss some weeds and have to spray again a few days later.
If you want to spray weeds after cutting your lawn, you should wait for at least five days for the weeds’ leaves to grow back first before spot spraying them.
What is the Best Time to Spray Weed Killer?
The period you have to wait before cutting your grass will also depend on a few factors.
First is the weather. When using liquid weed killers such as 24d, you should check the forecast to see whether it might rain on the day you intend to spray the weeds. If there are signs of rain or wind, you might want to hold off spraying your weeds first. Rainfall will dilute the weed killer you use, making it less effective on the plants.
If it rains after applying your weed killer, wait at least five days and observe how the weeds react to the herbicide, and then reapply if needed.
The second is the season. Liquid weed killer needs to dry on the plant to be effective. So applying it in winter or early spring may not be as effective as applying in summer and late spring. You can also use granular weed killers such as Scotts Weed and Feed during the wet months. Granular weed killer works best when the grass is wet, so you can water your lawn lightly before applying it.
Can you water lawn during summer
Remember, you shouldn’t disturb your lawn after spraying weeds. This doesn’t just mean you shouldn’t mow or water. It also includes keeping away any children and pets from playing on your lawn after you spray. The herbicides contain chemicals that are harmful to both humans and pets.
Lastly, hold off on watering your lawn after spraying weeds to avoid diluting the effect of the weed killer. You can water your lawn again after mowing.
Also read: What next after spraying weed killer?
Whether you use liquid weed killer or granular weed killer to control weeds is up to you.
However, ensure you read the herbicide label you settle on properly. Some weed killers may need several applications, which increases the period you need to wait before you mow.
So, how soon after spraying weeds can I mow? Two days is enough for the weed killer to act on the weeds. Mowing any sooner than that reduces the effectiveness of the weed killer.