Best Time Of Year To Aerate Lawn And Overseed?

So you have decided you think it may be a good idea to aerate and overseed your lawn as you have heard there are many benefits that will happen to your lawn after the process. Maybe you have bare patches on your lawn and you are looking for a solution without completely relaying your entire lawn.
This is a process that you will see good results from if you do it correctly and that is why I have made this article about the best time of year to aerate your lawn and overseed it.
Luckily if you get this process wrong and do it at the wrong time of year you won’t actually do any damage you just won’t see the maximum benefits you would have seen if you follow these instructions and do it at the optimum time for your area and variety of grass.
There isn’t really one answer for the best time as there are various factors you have to consider before you aerate and overseed.
Some of the factors you have to consider before aerating and overseeding are:
- Do you have cool season or warm season grass
- Your geographic location and local climate
Check out my article on techniques to make your lawn green naturally.
Why You Should Aerate…
It is definitely a good idea to aerate your lawn and overseed it on a regular basis, even if it already appears healthy.
When you aerate your lawn you are basically sticking spikes into it and making holes and this has many benefits. Aerating your lawn will result in the soil becoming less compacted especially if your lawn gets trampled on.
Having less compacted soil as well as the holes you create will allow water to more easily reach the root system and this will be a massive benefit to the microorganisms that live in the soil. These microorganisms are vital as they break down the thatch layer and this, in turn, releases vital nutrients into your lawn.
…And Overseed Your Lawn
Overseeding your lawn is a simple process that will improve the health of your lawn if it isn’t in tip-top shape and if your lawn is already in great condition it will help to keep it that way.
When you add fresh seed to your lawn the result will be that your grass grows thicker and this has several benefits:
- A lawn with thick grass will not be easily overtaken by weeds as weeds thrive when lawns are bare and in bad condition.
- Adding seed to your lawn will make it more resistant to infestations and disease.
- When your lawn is thick with healthy grass it just looks awesome and adds to the curb appeal of your property.
Fall Is The Best Time For Cool-Season Grasses
If you have cool-season grass on your lawn I would recommend that the best time to overseed is at the end of summer or early fall.
I recommend this time of year as your soil should have some moisture in it and the temperature should be beginning to cool down a bit compared to the middle of summer months which makes it kind of ideal.
Your seeds should have time to germinate and grow into grass at this time of year before the cold winter temperatures hit.
It is important you do not leave this important task until it’s too late in the season because if the frosty weather hits before your new grass has had time to grow and become settled it may not survive the cold weather.
If you live in an area that is good for cool-season grasses I’m sure you already know how devastating the cold weather can be.
Check out my ultimate guide for cool-season grasses.
Spring Is The Best Time For Warm-Season Grasses
If you are in an area that has the ideal climate for growing warm season grass then there will be a larger timescale for when is the best time to aerate and overseed. Due to the fact, your local climate is a lot warmer for a longer time period this results in a different best time of year for overseeding.
For warm-season grasses in areas with a warm summer climate you do definitely want to avoid overseeding during the height of summer as it will be too hot and if your grass does actually germinate and sprout, it will probably wither away before it grows into mature vibrant grass.
The best time to aerate and overseed warm-season grass is during the spring.
This is because there should still be some moisture in the ground and it should be hot enough for your seeds to germinate and start to thrive before the what can be devastating mid-summer heat arrives.
However, if your lawn has been getting trod on all summer and you would like to repair thin patches or you just haven’t got round to overseeding yet, you can always do this task in the fall just like you would for cool-season grass varieties.
Check out my ultimate guide to warm-season grasses.
Check out my article on how to make your lawn thicker and greener.
Best time to overseed lawns in the northeast
If you live in the northeast of the USA your local climate will be best suited to growing cool-season grasses.
The best time to aerate and overseed your lawn in the northeast of the USA would be during fall, just try and do it 6 weeks before the first frost.
Recommended cool-season grasses: Kentucky Bluegrass, Perennial Ryegrass, Tall Fescue, Fine fescue
Best time to overseed lawns in the midwest
If you live in the midwest of the USA your local climate will be best suited to growing cool-season grasses.
The best time to aerate your lawn and overseed it would be fall, just make sure you give your seeds enough time to start growing (4-6 weeks) before the frosty weather arrives.
Recommended cool-season grasses: Kentucky Bluegrass, Perennial Ryegrass, Tall Fescue, Fine fescue
Best time to overseed lawns in the south
If you live in the southern states of the USA then your local climate will be best suited to growing warm-season grass varieties.
The best time to aerate and overseed in the south would be during springtime. That’s because it will be warm enough for the seeds to develop before the real heat of the summer arrives.
Recommended warm-season grasses: Bermudagrass, Centipede Grass, Zoysia Grass, Bahiagrass
Best time to overseed lawns in the west
The best variety of grass depends on whereabouts in the region you live in. For the northern west you would be best-growing cool-season grass and south-west the best varieties would be warm-season grass.
If you live in the west of the USA then the best time to aerate and overseed your lawn would depend on where you are, north-western states would be spring, and south-western states would be fall.
Recommended cool-season grasses: Kentucky Bluegrass, Perennial Ryegrass, Tall Fescue, Fine fescue
Recommended warm-season grasses: Bermudagrass, Centipede Grass, Zoysia Grass, Bahiagrass
How Do You Aerate And Overseed Your Lawn?
It is actually quite a simple process to aerate your lawn and overseed it.
You can keep it really simple by using your garden fork and go over your whole lawn sticking it in the ground, this is the most simple way to do it. You should check out my full article on aerating your lawn with a fork.
If you want to invest in some equipment there is a large range with variable price points.
The cheapest equipment for aeration would be to get yourself a set of aerating spike shoes and simply walk all over your lawn or you could go for a top of the range core aerator that will remove cores (like little apple cores) and this is the best equipment to solve soil compaction issues.
When it comes to overseeding your lawn again there is different equipment you can use or you can use no equipment at all.
There is nothing to stop you from taking handfuls of grass seed and sprinkling them over your lawn, this works but you will probably end up with an uneven spread of seeds.
If you want to invest in some equipment then there is a large variety of spreaders on the market you can use to ensure you evenly spread the seeds over your lawn.
When I have spread seeds on my lawn I always rub a rake with the flat side down over my lawn as this helps the seeds work their way down to the thatch layer and that’s where you want them to settle and grow.
How Much Grass Seed For Overseeding
Check out my article on tips for aerating when you have a sprinkler system installed.
There is no general rule for how much grass seed you need to overseed your lawn as different sizes of lawn and different varieties of grass require different amounts of seed.
- You have to measure your lawn to calculate how much grass seed you will require to overseed it.
- To calculate the size you should measure two adjacent sides of your lawn. If your lawn is 5 feet wide and 10 feet long that would make your lawn 50 square feet.
- Seeding rates are normally calculated on a pounds per 1000 square feet basis, to get this number divide the square feet area by 1000. The above example would be 0.05.
- Now you have to multiply by either the number of 1000 foot sections or the decimal you calculated by the seeding rate for your specific grass variety.
Or you can enter your information into this grass seed calculator from lowes to get the result.
Can You Just Sprinkle Grass Seed On Lawn?
If you have some thin patches of grass on your lawn then that is probably the only time I would recommend just sprinkling some grass seeds.
When I spread seeds on my lawn I like to have an even spread and use a technique that gets the seeds down to the thatch layer where they can successfully grow.
The problem with simply sprinkling grass seed is that you end up with an uneven spread of seeds sitting on the surface on your lawn and you really do have to get them down to the bottom of your grass and away from the surface to have any success.