When Is the Best Time to Spray Weed Killer? (Seasons, Weather & Time of Day)

When Is the Best Time to Spray Weed Killer? (Seasons, Weather & Time of Day)

No matter of how considerably we combat off weeds, they make a comeback. It can come to feel like we’re in the battle on your own and weeds have anything particularly in opposition to us. Weeds are a problem for gardeners throughout the world, and we’ve received the selection of acceptable fertilization and irrigation, but numerous folks pick to spray weed killer.

Because which is the circumstance, we have to contemplate what time of the year is the very best to spray? What about particular climates or occasions of the working day? The ideal time to spray weed killer is generally spring but there are also basic safety concerns about our house that we have to contemplate and emergence herbicides.

Before You Spray

We need to have to comprehend how weed killers function ahead of we spray. How is it that a sprayed weed killer kills the weeds but not grass other plants? Weed killers interfere in the expansion of weeds by blocking protein production or destroying root development. Herbicides aren’t as hazardous to individuals as pesticides, but we require to spray weed killer with caution.

Pre- and Post-Emergence Herbicides

We can use pre-emergence herbicides on an established lawn to disrupt the weed lifestyle cycle, particularly for summer time weeds. Pre-emergence herbicides examples are benefin and dithiopyr. Time the spraying of weed killer just before weeds germinate, which is usually in early spring. Then, we can reapply the 7 days killer 8 weeks after the very first spraying.

For put up-emergence herbicides, we can use glyphosate chemical to get rid of weeds by absorbing it into the plant tissue. Glyphosate-based mostly chemical compounds achieve the ideal results when used to young weeds.

Safety Issues Around the Home

Not only must we safeguard ourselves when spraying weed killer by putting on extended sleeves, gloves and goggles, as properly as utilizing a respirator and protecting headgear, but we need to defend other people. We require to read through the label to know how long we need to continue to be out of the handled location, but before that, we want to keep animals indoors. Also, we need to have to hold youngsters absent from the sprayed spot before and right after, so they should be within throughout the spraying and steer clear of the location for the period specified on the label.

Tips & Tricks

Spraying by the Seasons

Although we may get attacked by weeds all-year-round, we require to strategize about when to spray weed killer to get the optimal impact. Let us go by way of our method for every period.


Weed killers function very best throughout hotter conditions, but that does not suggest we can not use it during winter. Then, we have to do is make sure that we spray during the middle of the day for the duration of sunshine. The substances may get rid of their efficacy if permitted to freeze overnight.


Spring is the greatest time to spray weed killer since it’s heat, and we have a opportunity in the course of early spring to utilize pre-emergent to prevent them from germinating. Then, we must implement the post-emergent 8 weeks later on to eliminate the far more stubborn weeds whilst they’re young.


If we’re going to spray in summer season, we need to have to make certain to do it at the end of the year. By managing weeds at the conclude of summer season, we’ll reduce the issue for subsequent spring. We should use an herbicide that kills a range of pest grasses and apply it in late early morning or early afternoon. The spray may evaporate in the warmth of complete sunlight.


This is a excellent time to spray weed killer simply because it’s when weeds are most vulnerable. By spraying publish-emergent, weeds will wrestle to survive winter season. We must implement two treatments in Oct, two months aside. If they really don't wilt quickly, we want to be individual till spring when we’ll see that most of them won’t return.

When Is the Best Time to Spray Weed Killer? (Seasons, Weather & Time of Day)
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Spraying by Time of Day

Not only are weeds more prominent during specific seasons, but they also have peak times in the course of the day that they prosper if we do not consider care of them.

Cold Climate

It’s pointless to spray weed killer when there is dew on the plants due to the fact the spray will turn into also diluted to be efficient. Harsh winters are also pointless if the floor is frozen or protected in snow. If there is no snow and the ground isn’t frozen, then the greatest time is mid-working day, with the sun out.

Temperate Climate

Since crops are minimum active from dusk until finally the adhering to morning after dawn, the best time to spray in a temperate local weather is in the late early morning or early afternoon.

Warm Climate

It is very best to treat when right away temperatures are in the reduced 70’s to 60’s. Daytime temperatures ought to be in the mid-80’s.

Weather Conditions

When Is the Best Time to Spray Weed Killer? (Seasons, Weather & Time of Day)
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Weather conditions has a significant position in the efficiency of spraying weed killer.


Spraying a plant soon after rain has fallen will dilute the weed killer and make it less efficient, so we ought to ideally wait around 24 hrs right after for the vegetation to dry. If the region receives a great deal of rain, we can decide for weed killers that are rainfast within 2-4 hours of spraying.


We require to decrease spray drift, which transpires when herbicide blows to other places of the garden throughout windy situations and kills unintended plants. There’s no point in spraying when the wind is powerful, so we need to have to hold out for it to relaxed, which usually transpires in the morning and at night.

Extreme Heat or Cold

Problems that are really sizzling or cold won’t perform due to the fact liquid evaporates prior to absorbing in really scorching temperatures and freezes in excessive cold.

Other Factors to Consider


The ideal year to spray the weed killer is in spring or fall. The explanation is that we must do it in warm temperatures but not when it’s very sizzling simply because the liquid evaporates or incredibly chilly so that it freezes. Spray the weed killer in early spring, then an additional software eight weeks later.

We can also do it in tumble, with Oct becoming the greatest month so that the weeds do not endure in wintertime. Two therapies that are two months apart in that month will generate the optimal end result.

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