When is the best time to spray for weeds? If I had a nickel for every time I was asked this, I could probably cater some delicious Gate’s
Barbecue for few hundred customers! But to answer this question, I am going to explain when to control 4 of the most commonly founds weeds in the lawn.
The best time to spray for weeds, in no particular order
Crabgrass might be one of the easier weeds to prevent and one of the most difficult to kill once it’s already come up. Nearly every lawn care program starts with crabgrass preventer. The reason for this is that by simply applying a pre-emergent in the spring, you can prevent the crabgrass from sprouting/growing for the entire year. If you, somehow, find yourself needing to spray for crabgrass after it’s already sprouted, then you’ll want to look for crabgrass killer that contains a specific herbicide called Quinclorac. Quinclorac is amazing when it comes to spraying for crabgrass! I must warn you that if the crabgrass has been mowed off several times already(usually by late July or later), you might find it difficult to kill due to the fact that it’s hardened off to the point of not being able to absorb the herbicide. The best time to spray for crabgrass is early in the summer when the plant is still small. The good news is that the plant will die at the first frost.
I consider dandelions to be one of the easiest weeds to control, but they can spread so easily once they’ve gone to seed. Only the most basic herbicide is required to control dandelions. Any weed killer off the shelf containing Trimec Herbicide will be enough to control dandelions. The difficult part of dandelion control is how easily and how far their seeds will travel once they’ve started seeding. You might think you have everything under control by the end of May, but once they go to seed in your neighborhood, you might see them popping up again in the fall. Not to worry though, aside from the extra work, they are still very easy to control in the fall.
White Clover is a fighter! Many weed killer labels might say they control clover, but I can tell you from experience that they aren’t that effective. As the weather starts to warm up, it becomes a very prolific grower and often times will not be affected by most weed killers. The best time to spray White Clover is before the temperatures reach the upper 80s. The best “made for retail” product that I can recommend is a herbicide called Turflon Ester Ultra. I have used it and it is often effective on clover during the warmer months when clover might grow right through the weaker herbicides. For the cooler months, I would recommend PBI Gordon’s Speedzone or Fertilome’s Weed Free Zone. Like the Turflon Ester Ultra, these are more likely to be found in the specialty garden centers.
Yellow Nutsedge is the biggest head scratcher of them all. Originally the experts said that Yellow Nutsedge thrived in poorly drained soil. This is absolutely true, but even now, it has spread into areas that don’t quite fit the description of “poorly drained”. This weed starts to rear its ugly head in late June and will grow until there’s a freeze. My advice on when the best time to spray for Yellow Nutsege is early and often. Certain herbicide products such as “SedgeHammer” are available through many specialty retail garden centers. SedgeHammer is very slow to work, but is effective at killing the existing weed. Any bottles of weed killer that are labeled for Yellow Nutsedge should contain a herbicide called Sulfentrazone. This is a faster acting herbicide that is very effective at killing the existing Nutsedge.
The bad news about Yellow Nutsedge is that even though you may kill the existing plan, new ones will likely pop up near the dead ones, making it a never ending task. Like crabgrass, Yellow Nutsedge becomes harder to kill after it’s been mowed a few times and will also die at the first frost.
Hopefully this help in your quest for a better looking lawn. For more information on some of these weeds, please check out my blog posts entitled How do I control Yellow Nutsedge, the worst weed in the world! and Crabgrass! The what, why and how of dealing with it.