It’s hard to believe that it’s almost back-to-school season! This busy time of year for many families is also a crucial season for caring for your lawn. The Green Care team will soon be tackling many important lawn care tasks for our clients. From N fertilizer and lime applications to core aerations, there is much to do in late summer and early fall to ensure the health of our clients’ turf here in the New River Valley.
We have talked a lot about the importance of core aeration. This process relieves compaction, opening up the soil to improve infiltration of water, fertilizer, and oxygen into the roots. We typically pair core aeration with another service called overseeding. We wanted to dive into that a little bit to explain why overseeding can be so important.
Weeds are the bane of every homeowner’s existence. No matter how meticulous your lawn care routine, they always seem to pop up and ruin your beautifully manicured grass. While there are several ways to get rid of weeds, like hand pulling or using herbicide, many homeowners are turning to overseeding as a natural way to crowd out and minimize weeds.
But will overseeding actually get rid of your weed problem for good? Let’s take a look,
What Is Overseeding?
Overseeding is the process of adding grass seed to an existing lawn. It’s done to increase turfgrass density, improve color, and fill in bare or thinning spots.
The goal is to get so much grass growing that there’s no room for weeds to creep in. When you overseed, the grass seeds you sow will germinate and the new seedlings will knit together with your existing grass to form a lush, thick lawn.
How Overseeding Helps Eliminate Weeds
There are a few ways that overseeding helps eliminate and prevent weeds:
-
It crowds them out By filling in bare spots and increasing turf density, there are fewer places for weeds to take hold The thicker your lawn, the harder it is for weeds to establish themselves.
-
It makes your lawn more competitive. Overseeding improves vigor, giving your desired grass a competitive edge over weed seeds. Healthy, dense grass will be better equipped to compete for resources.
-
It corrects issues that allow weeds. Fixing compaction, poor drainage, or nutrient deficiencies through aeration, topdressing, and fertilization provides a better environment for your grass to thrive, so weeds can’t gain a foothold.
-
It accelerates turf growth. Overseeding kickstarts rapid grass growth. The faster your lawn grows in, the less opportunity for weeds to invade.
So while overseeding itself doesn’t kill weeds, it creates conditions where weeds struggle to survive. A lush, dense lawn is a weed-resistant lawn.
When to Overseed to Prevent Weeds
Timing is key for overseeding success. In general, it’s best to overseed when:
-
Temperatures are consistently below 80 degrees F. Cooler fall temperatures allow for better seed germination.
-
Rainfall is moderate. You need moisture to germinate seeds, but overwatering causes issues.
-
Weed pressure is low. Overseeding when weeds are dormant prevents them from gaining a foothold.
The optimal time is early fall. But you can also overseed in early spring or late fall depending on your climate and turfgrass type. Just avoid overseeding in summer when weeds thrive.
Proper timing gives your grass the head start it needs to choke out weeds.
Does Overseeding Get Rid of Existing Weeds?
Unfortunately, overseeding alone won’t get rid of weeds that are already established in your lawn. The newly seeded grass generally won’t be able to outcompete mature weeds.
Before overseeding, it’s important to remove existing weed growth through:
- Hand pulling small weeds
- Selective herbicide spot treatment for larger infestations
- Power raking to remove thatch and expose weed roots
Eliminating current weeds prevents them from crowding out the new grass seedlings. Overseeding works to prevent new weeds but won’t remove mature weeds.
Overseeding Best Practices for Weed Control
To maximize the weed-fighting power of overseeding, be sure to:
-
Use quality grass seed suited to your climate. Improved cultivars germinate better and tolerate traffic, drought, and disease.
-
Prepare the soil by aerating, dethatching, and pH adjusting. This alleviates compaction, removes debris, and corrects issues for better growth.
-
Maintain proper watering schedules. Water lightly 2-3 times daily to keep seeds moist until germination. Then water deeply 1-2 times a week.
-
Allow 4-6 weeks before first mowing. Mowing too soon risks pulling up newly rooted seedlings. Let them establish first.
-
Fertilize 4-6 weeks after germination to feed new growth. Use a starter fertilizer to encourage root establishment.
Following best practices ensures your new grass grows in thick and strong, leaving little room for weeds to take over.
Alternative Ways to Eliminate Weeds
If overseeding alone doesn’t give you the weed control you desire, some alternative options include:
-
Preemergent herbicides: Applied in early spring, these prevent summer and fall annual weeds like crabgrass. Use alongside overseeding in fall.
-
Corn gluten meal: Works as an organic preemergent by inhibiting root formation in emerging weeds. Apply early spring and fall.
-
Vinegar: Non-selective herbicides like horticultural vinegar kill existing weeds via foliar application. Use for spot treatment of broadleaf and grassy weeds.
-
Soil solarization: Heating moist soil under a plastic tarp kills weed seeds and seedlings. Do for 2-6 weeks in summer to prep for fall overseeding.
-
Flame weeding: Uses a propane torch to scorch and destroy emerging weeds. Effective on young annuals.
An integrated approach combing overseeding with other methods delivers the best weed control. Overseeding strengthens your turf while other tactics target weeds.
Overseeding Works Over Time
While overseeding is an effective weed deterrent, don’t expect overnight results. It takes planning, patience, and persistence for overseeding to reach its full weed-fighting potential.
But the payoff is worth it. A lush, dense lawn that chokes out weeds year after year. By overseeding regularly, you can break the weed cycle and enjoy a thicker, greener, healthier lawn naturally with less weed pressure over time.
Overseeding gives your grass the competitive boost it needs to dominate rather than weeds. So while it may not eliminate every weed immediately, overseeding can significantly and sustainably reduce weed problems in your lawn when done properly.
Why Should I Overseed My Lawn?
Most homeowners consider overseeding when there are thin or bare spots in their lawns—be it from dry conditions, insects or disease, overuse, etc.— that they want to repair. This is a good reason to overseed; however there are other benefits to overseeding as well.
Overseeding improves and maintains turf density. This can prevent weeds, because a thick lawn is your best defense against weeds.
Overseeding can enhance the uniformity and color of your lawn’s appearance. It will give you a thicker, healthier looking lawn.
Overseeding can help your lawn better withstand tough conditions. Depending on your existing turf conditions and needs (age of turf, shade vs. sun, usage, etc.), overseeding new or different turfgrass varieties into your lawn may help it to better withstand elements such as insects, disease, drought, shade, and heavy traffic. Therefore, this overseeding could end up reducing the amount of fertilizer, water, and pesticides required to care for your lawn. If you’re unsure what kind of grass type you may be interested in, check out our blog post about how to select the right type of grass for your lawn. We’d also be happy to work with you to ensure that your grass type meets your overall goals.
What is Overseeding?
Overseeding is the periodic addition of grass seed to an existing lawn. While it can be done without turning over the soil (you can overseed by simply putting seed directly on your grass), pairing it with a core aeration makes it more effective due to the seed to soil contact. The new seedlings root into the aeration holes, allowing for better growth.
How Do You Reseed A Lawn That’s Mostly Weeds
FAQ
Do I need to kill weeds before overseeding?
Yes, it’s generally recommended to kill weeds before overseeding your lawn. This is because weeds compete with grass seeds for resources like sunlight, water, and nutrients, hindering the growth of new grass.
Does overseeding choke out weeds?
What is the best grass seed to choke out weeds?
To effectively choke out weeds, Zoysia grass is a strong contender due to its dense, spreading growth habit. Other options like Bermuda grass and St. Augustine grass also offer good weed suppression due to their aggressive growth.
What gets rid of weeds permanently?
There is no single permanent solution to getting rid of weeds, as they can regenerate from seeds, roots, or rhizomes.