How to Overseed Your Lawn
A thick, dense turf will not only look good, but help prevent pesky weeds from reaching the soil, geminating, and filling your lawn with unwanted invaders. Overseeding is the process of putting new grass seed down overtop of the existing grass in order to achieve this nice, thick lawn. Overseeding is not the only method in achieving such a lawn, but if your lawn is starting to look thin and bare, it's highly recommended. Here's how to get it done...
Step 1: Dethatch (Optional)
Unless your lawn is relatively new, it likely has a buildup of what is called, thatch. Thatch is a layer of both dead and living grass shoots, stems, and roots existing above the soil. Basically, if you can see any buildup that's not green below the blades of grass and above the soil, you've got thatch. This is normal and having some thatch isn't bad. Eventually, however, the thatch builds up and blocks the soil. When we end up putting down the new grass seed, we need it to be able to reach the soil and have good contact with it. Dethatching is the process of ripping all that thatch out. You can do a basic dethatch with a simple rake, or you could go as far as renting a dethatching machine. The latter option will look as if you're completely destroying the existing lawn, but have no fear, clearing up that thatch will give new life to the lawn and again let that new seed get in there, which will result in a thick new carpet of turf.
Step 2: Aerate (Optional)
Aerating is the process of pulling plugs out of the soil, which leaves behind holes all throughout the soil. Believe it or not, the blades of grass are not the only parts of your lawn that need air. Air is also good for the roots and soil. Over time, your soil is going to compact and get dense. If this is true for your lawn, you'll want to rent out an aerator or have a local company come do this before you put down the new seed.
Step 3: Scalp the Lawn
Scalping the lawn is another way of saying, "mow it super low." Here, we need to cut the existing grass low so we can see all those bare spots and so that the grass seed has plenty of room to make contact with the soil. With that being said, be sure to bag the grass so that the clippings don't cover the soil.
Don't be afraid to cut low enough to the point that you feel like you're harming the grass, especially if you are going to skip the dethatching step. Scalping the lawn can somewhat take the place of dethatching by cutting low enough that you are cutting into that thatch and sucking it up into the bag. A lot of people will avoid cutting this low because it feels like you're destroying the grass, but as long as you're not uprooting the plant, it will come back strong and better having that thatch removed.
Step 4: Remove Debris
You will have likely done a lot of this by bagging you do your scalping, but if there is any leftover clippings or debris, clean it up with a rake and/or leaf blower.
Step 5: Add Topsoil (Optional)
While your grass is cut nice and low, this is a great opportunity to top-dress your lawn with new, healthy soil. This soil will be a bit looser than the existing soil, which will make for a favorable breeding ground for the seed to grow into. This is also a great opportunity because you can flatten out any bumps or dips you have in your yard.
Step 6: Spread the Seed
First, make sure you know what kind of grass seed to get. Make sure you're subscribed to our site, because we'll post plenty of articles and discussions on choosing the the correct grass seed. In short, you likely want to use the type of grass that you already have in your lawn. A quick internet search should help you discern this. If you end up needing help, don't be afraid to reach out to a professional lawn care company near you.
To spread the seed, put it into a push spreader and start pushing! Be sure to reference the seed's packaging to see the correct application rate to set your spreader to. To get full coverage, you can walk in patterns similar to how you'd cut the grass.
You want to make sure the seed has good contact with the soil, so as an optional step, you could rent a roller and make sure the seed is pushed down against the soil. If you're not dealing with too big of an area, you could simply walk all over the seed or use something like a large PVC pipe in place of a roller.
Step 7: Cover with a Compost (Optional)
Once the seed is down, you can cover it with either a mushroom manure or peat moss. Either of these compostable materials will provide some coverage for the seed that will help it from washing away or getting toasted by the sun, but primarily you want to do this step so that the seed remains most. Manure and peat moss have a good quality that will retain and keep moisture in contact with the seed. Although we are saying this step is optional, it's not one we would skip.
Step 8: Fertilize (Optional)
Fertilizing the new seed isn't absolutely necessary, but there are a lot of "starter fertilizers" out there that will help boost the growth of the new grass. For personal, residential application, this is usually going to come in a granular form, so a push spreader is the best way to apply; just read the product directions and set your spreader to the correct application rate.
Step 9: Water!
The new seed has to stay moist in order to germinate and start its roots enough to be self-sufficient. In our experience, watering at least once a day for two weeks will get the job done. Conducting this process at the right time of year will also help. Ever notice the condensation on the ground in the Spring and Fall (depending on your climate)? This condensation will bring natural moisture to the seed every morning. Consequently, the morning is the best time to water, so if you happen to be unable to water, overseeding at these times of year will help. If you want to know more about when to overseed, stay tuned and subscribe, because we'll do an entire post about when to overseed and how to factor in your climate and grass type.
Final Thoughts
Overseeding is likely the answer if you find yourself fighting constant bare spots and weeds in your lawn. If you do it correctly, you'll end up with a thicker, healthier turf than you started with. If you are still left wondering about the process or what equipment you are going to need, check out our Overseeding buying guide.