Lawn care treatments are fruitless when performed at the wrong time of year. The best time to aerate and overseed a lawn is during the turf’s peak growing season. For cool-season grasses, this is in early fall. For warm-season grasses, this is between late spring and early summer.
Both aeration and overseeding help reinvigorate thinning lawns by exposing the soil to new grass seed. Aerate your lawn before overseeding for best results (overseed soon after aeration– don’t wait for the holes to close up).
We’ll explore how often you should aerate and overseed and when it’s too late to perform these treatments.
Understanding Aeration and Overseeding
What Is Aeration?
Over time, foot traffic and pet activity can compact soil, making it hard for water, air, and nutrients to reach grass roots. Aeration helps by loosening the soil, allowing the roots to grow, and improving the flow of water and nutrients. There are two main methods of aeration: core aeration and spike aeration.
Core aeration is the preferred method and involves removing plugs of soil from the lawn, creating space for nutrients to enter the soil.
Spike aeration simply uses spikes to push holes in the lawn, allowing water and nutrients to enter the soil. However, this method does not remove soil, making the soil more compact around the holes.
When your lawn needs some breathing room, aerating can help. Learn how aerating can benefit your lawn in our guide How to Aerate a Lawn.
What Is Overseeding?
Overseeding is a great way to give your lawn a boost. Overseeding means spreading grass seed over an existing lawn. This helps fill in bare patches and make the lawn appear thicker. With overseeding, you can improve your current lawn without tearing up existing turf or soil.
Note that this is different from reseeding which involves pulling up the grass, taking it back to bare soil, and planting new grass seed.
Giving your lawn a refresh doesn’t have to be difficult. You can overseed your lawn in just a few steps. Check out our guide How to Overseed a Lawn in 8 Simple Steps to learn more.
When to Aerate and Overseed Your Lawn
The best time to aerate and overseed your lawn depends on your grass type: warm-season grass or cool-season grass. You should aerate and overseed during your lawn’s peak growing season to allow it time to recover and maximize its growth.
For warm-season grasses, it’s best to aerate and overseed in late spring or early summer.
For cool-season grasses, it’s best to aerate and overseed in early fall. The second best time is in early spring.
Remember to aerate and overseed your lawn at the same time for best results. Aerate first, overseed second.
When Is It Too Late to Aerate and Overseed?
Once peak growing season has passed for your grass type, it’s too late to aerate and overseed your lawn successfully. Aeration is an invasive treatment, and your grass requires optimal growing conditions to recover successfully.
For cool-season grass, the peak season has passed by late fall and early winter. The cold temperatures and winter frosts will hinder seed germination.
The second window of opportunity for cool-season grass is early spring. However, once those warmer mid-spring temperatures arise, the heat will become too much for the cool-season grass to recover from aeration.
The peak season for warm-season grass is over by late summer and early fall. The warm-season turf will struggle to recover from aeration as temperatures drop, and the new grass won’t establish well.
Why Aerate and Overseed at the Same Time?
Aerating and overseeding simultaneously makes the most of each lawn treatment. Aeration loosens the soil, giving roots and seeds easier access to nutrients. By exposing the soil through aeration, more seeds will make contact with the soil, leading to more growth and thicker turf.
Since a thick, healthy lawn prevents the growth of weeds and the presence of disease, aerating and overseeding is a great way to make your lawn more robust.
How Often Should You Aerate and Overseed?
In most cases, aerating and overseeding once per year is sufficient. If you ensure that your lawn is regularly maintained and healthy and shows no signs of discoloration or stress, aerating and overseeding every two to three years may be enough.
Signs You Need to Aerate and Overseed
Unlike mowing or watering, aeration and overseeding is not a regular lawn maintenance task. Instead, it’s a once-in-a-while service that can boost the health of your lawn. There are a few simple ways to tell if your lawn needs overseeding and aeration.
- A thick layer of thatch has developed
- Soil that’s dry and hard
- Discoloration in turf
- Heavy traffic areas
- Thinning areas or uneven growth
Note: Aeration and overseeding improve lawn health, but you may need to enlist other methods in more dire cases. Check out our guide How to Revive a Dead Lawn.
FAQ About Aerating and Overseeding Your Lawn
Can you aerate your lawn too much?
Yes. Over-aerating can put excessive stress on your lawn and cause damage to your lawn.
Can you put down too much grass seed when overseeding?
It’s always best to read the label when overseeding your lawn. If you overdo it with the grass seed, your seeds may compete for light and nutrients. Instead of the lush look you were seeking, you’ll have a lawn that struggles.
Similarly, too little seed won’t make much of an impact, with thin and bare patches remaining the same.
How do you prepare your lawn for aeration and overseeding?
Ensure your lawn is clear of clutter and debris, including piles of leaves and tree branches. Before you begin, make sure you mow on the short end of the turf’s recommended height (without removing more than one-third of the grass blade) to ensure the grass seed reaches the soil.
Hire a Pro to Mow Your Lawn
If your lawn has seen better days, it may need more than a bit of water and fertilizer. Aeration and overseeding on their own are useful tools, but they become the ultimate lawn care power duo when paired together. Aeration can give your lawn a little more room to breathe while overseeding can thicken even the patchiest of lawns.
After you’ve reinvigorated your lawn with aeration and overseeding, you may need a helping hand handling the new turf growth. Hire a local lawn care professional who can maintain your lawn with regular lawn mowing services. Keeping your lawn looking sharp is just a few clicks or taps away.
Main Image Credit: The Toidi / Shutterstock
