This Powerful Herbicide Could Stop Pesky Crabgrass In Its Tracks

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Crabgrass is one of the most common lawn weeds that homeowners have to deal with. Due to the fact that it's a fast-growing weed that spreads quickly and thrives in warm, sunny, and compacted soil, crabgrass can be difficult to manage. While you may want to opt for natural management methods, such as making natural weed killers, there's at least one powerful herbicide available on the market that could stop that pesky crabgrass in its tracks.

Tenacity by Syngenta is an herbicide that claims to control pre- and post-emergence of over 46 different varieties of broadleaf weeds, including crabgrass. It uses mesotrione, a natural compound derived from bottlebrush plants, which inhibits the photosynthesizing capabilities of the weeds. Once fully absorbed by the weed, the herbicide cuts off the plant's ability to grow and reproduce, killing it completely. The result, in theory, should be a perfectly green, weed-free lawn.

With numerous — though not unanimous — 5-star reviews from customers on Walmart and Amazon, it's safe to assume that Tenacity could be one of the best weed killers for all your lawn problems. As one Walmart reviewer puts it: "I didn't know such an effective and selective crabgrass killer existed ... It didn't just kill some crabgrass, it eradicated it from my property entirely, and had no effect on the grass itself." Tenacity shares similar ingredients to other popular products, like Liquid Harvest Mesotrione, and is child- and pet safe once dried. Reasons enough, perhaps, to give it a try? 

One potential downside to this herbicide is the cost. A two-pack of 8-ounce bottles can set you back well over $100, while a gallon is priced at over $1,000. However, bear in mind that the formula is highly concentrated and will require diluting before use. You only need a teaspoon of Tenacity for every 2 gallons of water for spot treatment, so a little goes a long way. 

That said, there is more to using it than just diluting it in water. For example, you'll need additional additives before applying this herbicide to your lawn. To give the Tenacity an extra boost in preventing re-emergence of the weeds, you will need to pair it with a non-ionic surfactant. You should also add a lawn dye, like Liquid Harvest Lazer Blue, to the mixture in order to see where you've sprayed and thereby prevent overspray. This product is biodegradable and non-toxic, so you won't have to worry about it hurting your lawn.

To apply Tenacity to your lawn, fill a 2-gallon pump sprayer with water. Then, add the following measurements: 1 teaspoon of Tenacity concentrate, 2 teaspoons of surfactant, and 4 teaspoons of dye. Agitate the mix, then lightly spray it over the weedy areas of your yard. Only spray once, as overspray could cause grass damage. With luck, you'll never again see crabgrass in your yard.