Talk to any lawn guru long enough and they’ll eventually get around to complaining about the biggest problem they face, which is weeds. Although prevention is always better than spraying weeds once they are up, some weeds can be hard to prevent, and others have no preventers at all. Follow this guide to learn how to kill all of the basic weeds in your yard. 

Weeds fall into one of two categories:  grassy weeds and broadleaf weeds. A grassy weed is any weed that is a grass. Common ones include crabgrass, nutsedge, barnyard grass, and Japanese stiltgrass. A broadleaf weed is any weed that is not a grass. There are approximately 200 different broadleaf weeds that can grow in Northern Virginia. Among the most common are dandelions, wild violet, wild strawberry, clover, oxalis, spurge, lespedeza, hairy bittercress, and many, many, many more. If it’s not a grass, it’s a broadleaf weed! 

How do I treat Broadleaf Weeds in Lawns?

Killing broadleaf weeds is easy in the lawn. Herbicides with Carfentrazone (like Weed Free Zone or Speed Zone) are your best bet for selectively killing the weeds but not the grass. For almost all broadleaf weeds, using a pump sprayer, mix either an ounce of Speed Zone or an ounce and a half of Weed Free Zone in a gallon of water. Add in an ounce of Wilt-Pruf to make it stick, and you have a concoction that will kill anything that isn’t a grass. 

Please note that it said “anything that isn’t a grass.” Killing broadleaf weeds in the lawn is easy. Killing them in your flower beds is not. Almost all broadleaf weed killers are designed to protect your grass, but they don’t protect your plants in your beds. Anything that kills a broadleaf weed is going to kill your annuals, your perennials, your vegetables, and can even kill your trees and shrubs. 

Some broadleaf weeds are harder to kill than others. Tops on this list are Canadian Red Thistle, Wild Violets, and Wild Strawberries. For these extra hard to kill weeds, please add an extra half ounce of herbicide (Use 1.5 oz of Speed Zone or 2 oz of Weed Free Zone) and an extra ounce of 

Wilt-Pruf, which makes the herbicide last longer. Also be sure to follow all of the extra bonus steps listed below for the best success in applying an herbicide. 

How do I Treat Grassy Weeds in Lawns? 

Grassy weeds are harder to kill in a lawn than broadleaf weeds. Broadleaf weeds are different genetically from the lawn, grassy weeds are not. As a result, many grassy weeds require very

specific plans of attack. If you are trying to kill a grassy weed and having little success, bring a good-sized sample to Betty’s turf experts. We’ll make sure that we are talking about the right weed, and we will give you a plan of attack for going after the weed. 

For most basic grassy weeds, we recommend sulfentrazone, commonly found in Image All In One. Image All In One is best broad spectrum herbicide available for homeowners. Not only does Image kill most broadleaf weeds, but more importantly it kills basic grassy weeds such as crabgrass, nutsedge, and barnyard grass. 

When we get into other grassy weeds, although spraying can kill what’s there, sometimes other steps beyond killing need to prevent a weed from coming back. Japanese Stilt Grass can be killed with fenoxaprop (found in Bio Advance’s Bermudagrass Control for Lawns), but an annual pre-emergent applied in March and a refusal to ever mulch your lawn clippings back on to your lawn again are needed to stop the problem from coming back. Tenacity will kill poa annua and poa trivialis, but adjustments to the environment around your lawn including adjusting the soil and your watering habits are necessary. Bermuda grass (aka wiregrass) require a complete kill of the area, and please, don’t just use Round-Up alone, or the problem will be completely back in a year or two. Again, if you’re not sure, please bring a quality sample to one of the turf experts at Betty’s. 

Our Tips and Tricks for Treating Summer Weeds

When it comes to killing weeds, there are lots of additional helpful hints that will make sure your herbicide works as more effectively. Follow these steps for the best success at eliminating your weeds. 

1. Always use Wilt-Pruf. Wilt-Pruf will take your herbicide, spread it out so it covers the entire weed, and then laminates the herbicide on when it dries. Your herbicide is now waterproof, and you have greatly reduced the ability of the herbicide to drift to areas you don’t want it getting to. 

2. Broadleaf weeds tend to begin to appear in early spring. Almost all weeds you see in your yard through Memorial Day are broadleaf weeds. As the calendar turns over to summer, grassy weeds become more of a problem. As a result, Speed Zone is usually the answer to killing weeds the first half of the year, and the second half of the year Image All-In-One becomes a bigger focus. 

3. When spraying, go out first thing in the morning with morning dew. The presence of morning dew makes it clear that the grass is not too dry to be sprayed. If morning dew is present, then humidity is lower, another benchmark of when you should spray your herbicide.

4. Don’t spray in a drought. If it’s hot and dry out, wait until we get a solid rainstorm before spraying. First off, spraying when it is dry out can put too much stress on the good grass, and your selectve herbicide is suddenly not so selective. Also, herbicides work by attacking the new cells of a plant as it grows. If it is dry out, your weeds aren’t growing very much, which makes it harder for the herbicide to attack. 

5. Watch the temperature, but not too much. Some older herbicides have very limited temperature ranges where they work. Modern herbicides aren’t quite as limited, but we still want it to be above 40 degrees out before we spray Speed Zone or Image. We also don’t ever want to be spraying weeds if it is incredibly hot out (90 degrees Fahrenheit and higher). 

6. During colder seasons, trick your weeds into thinking it is warmer than it is by using warm water in your sprays. The weed will think it is warmer out, it will start growing, and the herbicide will be at the correct temperature to attack. Unfortunately, there is no corresponding trick for a mid-summer heat wave. 

Weed control involves identifying your weeds, then knowing which chemical to apply and when. By doing it correctly the first time, homeowners are spared much time, aggravation, and expense.