What to Do About Weeds and Thatch

Mowing, fertilizing, and watering are the first line of defense for a great lawn. However, every now and again you may have a problem with weeds or thatch.

 

There are different types of weeds that may pop up in your yard. Before you can get rid of them, it’s important to identify which type of weed you’re dealing with, as they require different control strategies.

 

Annual Grassy Weeds

One of the most common annual grassy weeds is crabgrass. Crabgrass grows from seeds each spring. Over the summer, they produce new seeds and then die after the first couple frosts. The seeds produced during the summer will germinate the following spring to repeat the cycle. While a vigorously growing lawn will make it difficult for crabgrass to grow, sometimes seeds may blow in from your neighbor’s lawn.

The best means of breaking the cycle of annual weeds is to use a pre-emergent herbicide. However, pre-emergent herbicides do not kill existing weeds. Pre-emergent products work by inhibiting a key enzyme that aids in the germination of the seed. These products are most effective when applied prior to germination, so you need to apply it in early spring and early fall. Be sure to read the label for application instructions.

 

Annual Broadleaf Weeds

Annual broadleaf weeds grow from seeds each year. Most often, they are found in recently seeded or thin and unhealthy lawns. Pre-emergent herbicides may keep some of these plants from growing, but once the weed is large, herbicides are often ineffective. Once they have reached this stage, the most efficient means of control is to pull the weeds by hand or cut them back frequently, so they are unable to produce new crops of seeds.

 

Perennial Broadleaf Weeds

Perennial broadleaf weeds, such as dandelions, regrow from their roots and will return year after year. Fortunately, there are several ways you can handle these kinds of weeds. For just a few broadleaf weeds, you can pull them out by hand—making sure to get the root out.

If the problem is widespread, an application of herbicides is most effective and less likely to damage your other plants. There are many products that will treat such an infestation in a granular or liquid form. When applied correctly, these products will not harm your lawn. When choosing one of these products, be sure to read the label in its entirety and make sure it’s safe for your species of lawn. Apply at the recommended rates and make sure to follow all instructions. Do not use a total vegetation killer on your lawn.

 

Thatch

Thatch is a combination of dead and living grass shoots, stems, and roots that are tightly knitted together that collect between the actively growing grass and the surface of the soil. A thick layer of thatch can prevent air and water from transferring to the soil and decrease the effectiveness of fertilizers and pesticides.

Thatch can become a problem in lawns that receive excessive fertilizer. Correct lawn care will help reduce thatch buildup. If you suspect thatch is becoming a problem in your lawn, dig out a small section of lawn and look for a layer between the soil and green grass leaves.

If the layer of thatch is under a half inch thick, aerification is the best solution. Aerification is the process of removing small columns of soil from your lawn to decrease soil compaction and increase air movement in the soil, subsequently reducing thatch. If the thatch layer is thicker than half an inch, you will most likely need a power rake or de-thatcher. These motor-driven machines look like little lawn mowers and can help draw the thatch out.

The best time of year to de-thatch your lawn is when the grass is actively growing during the cooler weather in April or October. De-thatching and aerification equipment are usually available for rent at reasonable rates at large garden centers and equipment rental firms.

 

The Benefits of Mulch

Spreading mulch around trees and in shrub beds provides several benefits. Besides being aesthetically pleasing, mulch enriches the soil and inhibits weed growth. Make sure to use natural bark mulch, as rock mulch does not inhibit weed growth nearly as well.