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When to Spray Weed Killer: The Best Time to Spray Weed Killer

When to Spray Weed Killer: The Best Time to Spray Weed Killer

Maybe you’re wondering what time of year you should apply your pre-emergent herbicide. Or, perhaps you’re dealing with a persistent weed problem and have decided to spray a weed killer, but want to wait for the optimal conditions. Either way, you’re wondering - when is the best time to spray weed killer?

We’ll discuss the role of timing in applying weed killer below, including when to spray weed killer to prevent weed growth at the start of the season and the ideal environmental conditions to wait for - dry, calm weather.

For more tips on how to kill weeds continue reading below. Or, get started on the right foot today with the strongest weed killer the UK has to offer, exclusively at Jennychem!

When is the Best Time to Spray Weed Killer in the UK?

Figuring out when to spray weed killer is a nuanced topic, as it depends on the growth cycle of the weeds you’re trying to control, weather patterns, and the specific type of herbicide you’ve selected for the task. 

Proper timing can not only enhance your success in applying weed killer, but it’s also a matter of safety - as suboptimal conditions can cause the weed killer to drift towards beneficial plants you want to keep, or worse, get ingested by people (including yourself). 

Don’t worry - we’re here to help you avoid all this. Let’s start by talking about the time of year.

Time of Year 

The most effective time to apply weed killer generally aligns with the active growth phases of weeds during the year. In the UK, this typically means the late spring through to early autumn.

  • Spring (March to May): This is the best time to apply pre-emergent herbicides, which are designed to prevent weed seeds from germinating. This type of weed killer should be applied just as the soil warms up but before the weed seeds have a chance to sprout. This is also a good time to tackle early-growing perennial weeds that begin to show after the last frost.
  • Summer (June to August): Post-emergent herbicides are most effective during the summer, especially when weeds are actively growing and most vulnerable to chemical treatment. This is when widespread weed infestations can take advantage of the warm weather and grow vigorously.
  • Autumn (September to November): Autumn applications can address perennial weeds in preparation for the next year. This application weakens the weeds before they enter winter dormancy and will reduce your weed burden for the following spring.

Optimal Weather Conditions

Beyond the time of year, figuring out the best time to spray weed killer requires an understanding of the ideal weather conditions. As we briefly mentioned from the start, you should wait for a dry, calm day - here’s why:

  • Dry Conditions: Herbicides should be applied when there is no rain in the forecast for at least 24 to 48 hours after application. This prevents the herbicide from being washed away by rain so it can be absorbed by the weeds.
  • Calm Days: Avoid spraying on windy days to minimise drift that can carry the herbicides to non-target plants, which could be damaged in the process. Drift also puts humans and pets at risk of inhaling or ingesting the weed killer, which is far more concerning.
  • Temperate Weather: While weed killers can be applied on warm days, extremely high temperatures can cause the herbicide to evaporate too quickly and reduce its effectiveness. On the other hand, chilly weather can slow down the action of the herbicide. Wait for the sweet spot where temperatures are moderate.

More Tips on Successful Weed Removal

Now that you know when to spray weed killer, let’s get into the application side of things so you can feel confident putting this problem in the past once and for all. From choosing the right weed killer to actually using it, here’s what you need to know.

Choosing an Effective Weed Killer

Picking the right weed killer is just as important as knowing the best time to spray weed killer. You need to choose a solution that aligns with your weed type and the conditions around your weed.

For instance, the ideal weed killer for broad leaves like dandelions and clovers will not be the same as the optimal product for grassy weeds like crabgrass. Figure out what you’re up against - then you can determine whether you need a selective or non-selective herbicide.

Selective weed killers target specific weeds without harming surrounding plants, so they’re great for lawns and ornamental gardens. 

Conversely, non-selective herbicides kill nearly all plants they come into contact with and are useful for clearing areas where you want to start anew or aren’t concerned with growth, like a driveway or walkway.

You’ll also need to choose a mode of action - either contact or systemic. As the name suggests, contact herbicides kill only the parts of the plant they touch, so they are fast-acting but may require repeated applications to deal with regrowth. 

On the other hand, systemic herbicides are absorbed by the plant and transported throughout its system, leading to a more thorough kill right down to the root.

Research the persistence of the product you intend to use, as some products break down quickly in the environment while others have residual effects that prevent weed regrowth for an extended period.

This is also a good time to assess the environmental side of things, especially if you have children or pets running around your yard. You don’t have to stress about toxicity or runoff if you use a product free from harmful chemicals.

Finally, think about how easy a product is to apply. Some products come ready to use with their applicators, while others might require mixing or special equipment like sprayers. 

Choose a product that you are comfortable handling and that suits the size and accessibility of the area you need to treat.

Put Weed Problems in the Past With the Help of Jennychem!

If you want to start off on the right foot and say goodbye to weeds for good, look no further than Weedex available at Jennychem. It’s backed by thousands of five-star reviews and can be used to control everything from Japanese Knotweed and Ivy to Horsetails, Nettles, Oxtails, and more.

This extra-strength formula targets the weeds at the root for rapid removal, putting these unwanted pests in the past once and for all. It’s also very easy to use, especially when paired with one of our garden sprayers, such as the IK sprayers lineup. We’ll walk you through the process below.

Application Guidelines

  1. Preparation: Ensure the area you intend to spray is moist but not overly saturated. This helps the herbicide penetrate the soil and plant tissue more effectively. 
  2. Mixing: Depending on the severity of your weed problem, Weedex Super can be used neat for intensive action or diluted 50:50 with water for regular maintenance.
  3. Application: Use a garden pump-up sprayer for even distribution, or apply directly to the roots with a watering can for targeted action. Cover all weed foliage thoroughly to ensure the herbicide is absorbed.
  4. Timing: Remember the best time to spray weed killer is not during windy conditions or when rain is expected within 48 hours. Early morning or late afternoon applications are ideal to avoid rapid evaporation.
  5. Safety: Avoid spraying near water bodies and ensure the area is dry before allowing pets or children to enter.

Prevention Strategies

You know what they say - an ounce of prevention is worth a pound of cure. You can take measures like incorporating mulch into your garden care routine to suppress new weed growth by blocking sunlight from reaching weed seeds.

Other physical barriers such as landscape fabric can be used to block weed growth in garden beds, protecting veggies or other plantings. You can also try laying out natural remedies such as corn gluten meal to prevent seed germination.

It’s also worth picking weeds by hand when you have some time to kill and want to get some fresh air. This is the safest, most effective way to ensure the complete removal of larger weeds that have a strong root system.

Ultimately, though, using Weedex Super in conjunction with our advice on when to spray weed killer will help you overcome even the most challenging weeds - so get to work!

Wrapping Up Our Guide on When to Spray Weed Killer

So, when is the best time to spray weed killer? In conclusion, there are a few times of year you should apply an herbicide - early spring through autumn when weeds are actively growing. 

Beyond the time of year, think about the optimal conditions for when to spray weed killer as well. Choosing dry, clam days will prevent the concerns of drift and ensure the herbicide adheres well to the weeds.

Our blog has more resources on keeping weeds at bay, such as using salt to kill weeds or how long for weed killer to work. You can also learn about all aspects of home and vehicle care with tips on how to melt ice on concrete, how much Adblue to add, where does antifreeze go, and more.

Remember, the strong weed killer you need to effortlessly eradicate even the toughest weeds is just a few clicks away at Jennychem. Our solution is trusted by more than 10,000 gardeners and is backed by a reputation for consistent results. 

Order yours today and see firsthand what a difference it can make in your weed management and prevention strategy!

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