Maybe it’s the brown patches in your lawn that are getting to you, or the grass just isn’t as green as it is on the other side of the hill. Either way, you want fix the problem, but there’s a lot of information and even more misconceptions out there about how to reseed a lawn. Here’s some solid intel on how, when and why you need to reseed your lawn.
Why Reseed your Lawn?
What are the reasons to reseed a lawn, and how can you tell when it’s needed? If your lawn is brown through particular times of the year, you may want to interplant grass that will grow well during that time of year. Has there been extreme weather that could cause plant stress or kill patches in your lawn? That’s another great reason to reseed. Maybe you just want to start filling in some thin spots, or add a better texture of grass to your lawn; these are also good times to reseed your lawn.
If there are particular conditions in parts of your lawn, like low areas that collect water, a heavy thatch covering, soil compaction from vehicles or heavy foot traffic or poor pH or fertilization issues, you will want to correct those before replanting. Putting down more seed in an area where the plant is failing to thrive is throwing good seed after bad.
When to Reseed your Lawn
There’s actually more than one good time to reseed your lawn. Part of how to reseed your lawn depends on what grass you have in your yard. If you only have cool season grass, turning brown in the summer, you can reseed with a warm season grass a few weeks after the last frost of spring. The warm season grass will keep your lawn green during the summer and the cool season grass will flourish in the spring and fall (also during the winter for southern locations). If you have warm season grass planted exclusively, you can do the opposite and have a lush green lawn through most of the year.
While warm season grasses are typically only planted in late spring, cool season grasses can be planted in spring or fall, usually three to four weeks away from your area’s average frost dates. Fall plantings tend to do better, especially when you’re learning how to reseed a lawn, as it will have a chance to establish itself during the fall, grow intermittently during warm spells in the winter and get another flush of strong growth in the spring before the summer stresses the plants.
How to Reseed your Lawn
Now that you’ve sorted out the why and when, it’s time to look at how.
To start with, you’ll need to prepare the area you’re going to reseed. To allow the grass seed the best chance to grow, start by mowing the existing grass down to 1.5″ to 2″ tall, allowing more light to enter the leaf canopy and reducing competition from the existing grass. Blowing off the lawn and dethaching the lawn and aerating it will give the new grass seed better soil contact, increasing it’s germination rate and allowing it to send down stronger root systems.
If you’re only taking care of a small patch, you can use a rake to clear the soil surface and break it open lightly. After broadcasting the seed, use the rake to gently work the seed back into the soil.
If it’s a larger area you’re dealing with, you’ll want to use a core aerator and go over the area to be seeded three to four times, creating 20 to 40 holes per square foot. After broadcasting the seed, drag a piece of chain link fence, a harrow or similar tool to break up the cores and incorporate the seeds into the soil. You could also seed a larger area using a grain drill or slit seeder.
Now that you know how to reseed a lawn, you’ll want to keep the area moist for the best germination rates. Watering a small amount of water once or twice a day will suffice unless you’re in a very dry climate. Continue mowing the lawn to a height of 1.5″ to 2″ until the new grass has reached the same height, and then slowly increase the height up to between 2.5″ and 3″. About six weeks after the new grass germinates, apply one pound of nitrogen to every 1,000 feet to keep it growing well.