Sod overseeding is the process of planting grass seeds into an already existing lawn without any major disturbance to the sod.
Filling vacant and bare areas in a yard to thicken the lawn, improve color, and introduce new, robust grasses into the lawn.
Overseeding is a great choice for someone with a lawn that has been damaged by insects or disease, drought stress, or just signs of decline, such as thinning and sparse grasses, brown or bare patches of soil, or just a lack of color.
When grass has died, you have two choices:
- lay new sod (or turf)
- overseed the existing sod (or turf)
This could be due to a very small area of your lawn that has died, not justifying a full installation of new sod.
Overseeding your yard with new and improved turfgrass varieties is often the best solution to thicken your lawn and improve its health and appearance.
Typically, new turfgrass varieties are more resistant to disease, drought, and damaging insects.
What to Consider Before Overseeding Dead Sod?
Excessive Moss Coverage
Too much moss indicates other problems, like too much thatch on your lawn and soil compaction,Neither of which is a good thing.
This will stop new grass seed from contacting soil, consequently germinating.
So if you have an excessive amount of lawn moss, you should take care of it first. Start by raking as much as possible.
After that, use a good moss killer before raking again to kill any moss, that stills remains.
Excess Lawn Thatch
Thatch is the build-up of dead organic matter in the crowns of grass plants.
It is made up of dead grass, yard waste, and other organic matter that has not yet decomposed.
Thatch serves a useful purpose because it protects the crown of the grass plant from physical damage and disease.
However, an excess of thatch can prevent air, water, and nutrients from penetrating the soil profile and can inhibit grass growth.
With thatch serving as a barrier to new grass seed and soil contact, seed would not germinate.
Compaction of Soil
When soil particles are compressed they push out air, water and nutrients, making it hard for them to get into soil.
This also makes it difficult for new grass seeds to germinate because they cannot grow roots when soil is this compacted.
A hollow-tine aeration allows soil particles to relax and loosen from each other.
This allows air, water and nutrients to go into the ground, making it more favorable for grass roots to grow roots and establish themselves.
Condition of the Soil
Grass is a resilient plant that can grow in dry states.
If you have very heavy clay soil, adding sandy loam topsoil would be beneficial.
Also, if the soil is very sandy, then a high quality loam topsoil would also be beneficial.
At a minimum, you should make sure the soil gets all of the nutrients it needs.
How to Overseed Dead Sod?
Step 1
The grass must be cut considerably shorter.
Mow the grass on a high setting if it is really long, cutting off only about a third of its length. Mow it a second time immediately after, but this time with a lower setting.
Mowing lower over time will avoid damaging the excellent sod.
Step 2
Use a rake to remove both thatch and grass clippings.
Thatch is primarily a layer of decaying organic matter and herbaceous material on the soil surface. After cutting the lawn, you will also need to remove all cut grass.
If there is a thick layer of thatch or cut grass, seeds will not germinate because seeds must be in contact with the soil to germinate.
Step 3
Scarification should then be applied generously. Seed will not germinate if grass seed is sitting on dead grass.
By heavily scarifying, you can guarantee that the soil will be exposed and that dead grass can be removed.
Step 4
Loosen the soil in the way that is best for the compactness of your soil.
There are other options for loosening the soil such as heavy raking, aerating, Roto-tilling, or a dethatching machine.
Step 5
Use a lawn starter fertilizer to give the new grass a good start.
Some grass seeds come with their starter fertilizer already connected to it. Be sure to check the grass seed package to see if it does have starter fertilizer.
Step 6
Use your hands or a mechanical spreader to spread your grass seed.
Don’t be shy when you let down grass seed. You can spread more than you think you need.
Grass seed does not cost much, so put more down, knowing that not all seed will germinate.
Step 7
Apply a light dusting of topsoil onto your seed.
The soil will need to be no thicker than a few centimeters. Visually you should imagine powdering your newly sown seed with a light dressing of topsoil.
Step 8
For small overseeding areas, utilize a binder that is used to keep the seeds from washing away.
This very much includes its blend of seeds, fertilizer, and soil mixture that will help with germination.
Again, it ideally keeps the seed moist – and with this product, seed germination is fast!
Step 9
Loosely rake the freshly seeded area to ensure the seed makes contact with the soil.
Seeds that are not in contact with soil will not germinate, just a visual representation with some whole corn kernels.
Step 10
To prevent birds from eating your seeds, cover them with garden fleece.
This will also increase the surface temperature and speed up germination. Once your seed has germinated, take off the fleece!
| What to do before overseeding | What to do after overseeding |
|---|---|
| Examine your lawn for the presence of thatch | Water the lawn immediately after overseeding to help grass seed settle into slits or aeration holes. |
| Aerate your lawn if it is too dense | Before grass seeds germinate, water the lawn lightly every day for one to two weeks |
| Remove the thatch and dead grass from your lawn | After the grass seeds germinate, gradually reduce the frequency and depth of watering |
| Cut the grass short with your mower on the lowest setting. | On your first mow, bag the clippings and don’t cut more than 1/3 of the new grass blade |
| Remove the clippings so that the grass seed can be viable | Regular lawn irrigation, mowing, and maintenance can resume after your first mow. |
| Rake your lawn to loosen the top layer of soil. |
Why You Should Overseed Dead Sod?
You did not achieve your beautiful lawn by accident (or over time).
The secret to a green, lush lawn is actually hard work.
In fact, if you perform a relative handful of landscaping tasks at the right time of the year, you will have the yard of your dreams in a season or two.
What most people recommend is to believe in an idea, which is asked of everyone on every level of life – overseeding your lawn.
The benefits of overseeding your lawn are numerous:
- The main purpose of overseeding is to rejuvenate worn out lawns. It is an easy way to repair a lawn back to beautiful, lush, thick, green, grass without the necessity of laying down new sod or installing sod.
- Sowing new grass seed over your existing lawn will enhance and strengthen your existing lawn against insects, prolonged drought, diseases, or any other harsh circumstances that may be contributing to your lawn struggling.
- Overseeding is a natural and affordable way to reduce pesticides, fertilizers, and water usage.
- Overseeding improves lawn color and uniformity. In fact, overseeding can help reduce weed growth by thickening and adding structure to the grass canopy, preventing light from penetrating the soil and allowing weeds to grow.
Is There a Specific Time to Overseed Dead Sod?
Selecting an appropriate season for this task is vital to enhancing your likelihood of success in replacing dead grass in your lawn with healthily new grass.
The perfect happens in the earliest of spring or the end of summer.
Your geography will dictate when you should overseed your lawn.
For northern cooler climates, the best time of year to overseed is late summer to early fall:
- This is because the weather should be pleasant and not too hot.
- The soil is warm enough to allow for germination during fall, but the temperatures won’t be so cold that the delicate new grass isn’t able to grow before winter arrives.
- For newly seeding it is also better because the weeds will not be growing as much as they could in the spring and summer.
- There is typically more rain than in the summer, allowing your seed to be moist and germinate.
If you don’t overseed during the fall do it as early as possible to provide seedlings enough time to establish before the heat of summer.
If you cannot overseed the sod in early fall the next best time is in the middle of spring. Wait until the grass begins to grow.
Face it, we overseed in the summer only really as a last resort because it is usually too hot to keep seeds moist, and with the weeds actively growing, your seeds are competing with both the weeds and themselves! It is a battle that the weeds will win every time.
What to Do after Overseeding Your Sod?
To support germination, keep your lawn wet following overseeding.
This is simply done with a watering system, but you have to either use a sprinkler or hand-water on smaller areas.
Do not stop watering as soon as you see the seedlings appear. The tiny seedlings still require your care during the first eight weeks.
The seedlings can dry out and die without a mature root system.
You do not need to apply a starter fertilizer when overseeding. Generally, if you fertilize your lawn, the soil will have sufficient nutrients for the new seed to grow.
If you fertilize your lawn after overseeding, then it can create competition with the mature grass, which is difficult for the new seedlings to establish.
Final Thoughts
Overseeding is a method for fixing thin and bare spots in lawns.
It is called reseeding as well. Lawn restoration must be done every so often and choosing the correct grass seed is critical.
There is no doubt that the best time to overseed a lawn is early fall. August 15 to September 15 is the sweet spot for most northern areas of the USA.
At this point in the year, daytime temperatures are still conducive for growth and the nights are cooler. This will cool down the new seedlings a bit from the heat during the spring.
Soil temperatures are also spot on which leads to faster seed germination.