When is the Best Time to Plant Grass Seed?

planting grass seed

One way to turn a thin, patchy lawn into a beautiful and lush one is by planting grass seed. But before you bring out the grass seed and bust out the seed spreader, take a second to think about when you should seed your lawn. The seeds germinate better during certain times of the year, and the best time to plant grass seed will depend on a few factors.

Read on to learn more about when you should plant your grass seed and why in this article.

The best time to plant grass seeds

sparse grass in need of overseeding
Photo Credit: John Mounsey | Pixabay | License

If you want to give your grass seed the best time at sprouting, you’ll need to consider your location and the type of grass. Your location dictates what grass you likely have on your lawn. Knowing what type of grass you have is important as cool-season grasses and warm-season grasses germinate best at different times of the year.

If you live further north, you likely have cool-season grass that can survive the harsh winter months. If you live in the South, you probably have warm-season grass that can handle the scorching summer heat much better.

What if I live in the middle? Most of the Midwest and Mid-Atlantic lie in the transition zone, where the temperatures can accommodate both cool-season and warm-season turfgrass. Some homeowners opt for just cool-season or warm-season grass, but you also can have a blend of both.

When to plant cool-season grass seed

growth of cool season grass
Infographic by Juan Rodriguez

The best time to plant cool-season grasses is late summer or early fall when the soil temperature is around 50 to 60 degrees Fahrenheit (60 to 75 degrees Fahrenheit air temperature). Cool-season grasses, like Kentucky bluegrass, fine fescue, tall fescue, bentgrasses, and perennial ryegrass, sprout best around this time of year. 

The exact time when you should plant your grass will vary a little based on where you live:

  • Homeowners above the transition zone will have cooler temperatures earlier in the year and can plant grass as early as Aug. 15. However, they have to plant their seeds by Oct. 1.
  • Those living in the transition zone need to wait longer. They should plant their cool-season turf around Labor Day up to late October

You want to plant during this time because it gives your new grass enough time to establish before the winter months. It will have an easier time doing this as fall is one of the active growing seasons of cool-season turf. Here are some other benefits to planting in late summer and early fall:

  • The temperatures are perfect. Your lawn soil will still be quite warm (but not hot) from the summer. Warm soil helps with grass seed germination. There’s also very little risk of sudden spikes in warmth that the tender seedlings may not survive because the temperatures will only get cooler from here on out.
  • There is rain, but not too much rain. The last weeks of summer up into fall are usually quite rainy. Light rain is a welcome sight as it helps keep the ground moist but won’t wash away the grass seeds.
  • Your grass has a better chance of survival. Most cool-season grasses are more cold-tolerant than they are heat-tolerant. Planting in the fall means your new grass will have to deal with a cold winter rather than a scorching summer early in its life. They will be more likely to survive and live to see the next active growing season (spring).
  • There are fewer weeds. There won’t be as many weeds during the fall and winter months compared to the spring and summer months, so your new grass will have less competition.

Note: You must plant your cool-season grass no later than 45 days before the first frost date. If you plant too late, the seedlings may die (if they sprout at all).

The second-best time to plant cool-season grass is spring after the soil has warmed up to 50 to 60 degrees. Usually, the soil reaches this temperature around April, so you may want to plant your grass seeds from April 1 to May 15. Any later than that may not allow your grass to establish before summer.

Note: You may have to wait longer before planting if you live further north. Always check the soil temperature to see if it’s warm enough before planting your seeds.

Spring is a decent time to plant grass because it also has cooler temperatures (like fall). But unlike fall, spring is harder to plant seed:

  • There are more weeds. Many summer annual weeds pop up in spring; some start growing even before it’s warm enough for you to plant your grass. This means more competition for nutrients and other resources.
  • Spring weed control can mess with your seeds. If you plan to control weeds in the spring, then you’ll have to wait before planting anything on your lawn. Many weed killers will mess with seed germination for up to a month – even up to four months for crabgrass preventers.
  • It’s too wet. Your lawn’s soil is more likely to become soggy and muddy in the spring thanks to a combination of seasonal rain showers and melting snow. An overly wet environment can lead to fungal diseases, seed displacement, and seed rot.
  • Your grass will have to face summer so soon. The heat of the coming summer will stress out your cool-season grass because it’s not very heat-tolerant. Planting too late also will put your grass at risk of not establishing before the summer.

When to plant warm-season grass seed

growth of warm season grass
Infographic by Juan Rodriguez

The ideal time to plant warm-season grasses is late spring or early summer when the soil temperature is hovering around the 65- to 75-degree range (about 80 degrees Fahrenheit for the air temperature). The grasses that sprout best during this time of year include Bermudagrass, bahiagrass, buffalograss, centipedegrass, and Zoysiagrass.

The exact time when you should plant will depend on how far south you live. Homeowners living in the transition zone will need to wait until May before they can plant their seeds, while those further south can plant much earlier, possibly in March

Here are the benefits of planting your warm-season grass in late spring and early summer:

  • Your grass has time to establish before winter. As long as you plant your grass no later than 90 days before the estimated first frost date, your grass will have enough time to establish itself before winter. Your grass will need time to grow a strong root system to survive winter dormancy.
  • It’s not too hot. These times of the year will be warm enough to encourage germination, but not yet scorching hot. Your new seedlings will have to endure the peak of summer heat if you plant too late in the summer, which will stress them out and possibly kill them. While they are heat-tolerant, they still need time to grow strong roots to survive the heat.
  • There is some seasonal rain. Light rain will help keep your seeds and seedlings moist, which is key to their survival.

Note: Those who live in areas with relatively consistent temperatures and mild winters can even plant as early as early spring to as late as fall.

How do you plant grass seed?

close-up of grass seed
Photo Credit: anasimin | Canva Pro | License

Planting your grass seed at the right time is only one factor that influences how well your seeds germinate. Here is a simplified guide on how to grow grass seeds:

  1. Choose the best grass seed for your lawn. Take your location into account as well as how maintenance-heavy you want your fully grown grass to be in the future. You also will want to consider how much shade and foot traffic your lawn will get.
  2. Prepare your lawn. 
    1. Perform a soil test to determine your soil’s pH and nutrient levels so you can adjust them before planting.
    2. Level your lawn and remove rocks and pebbles before planting your lawn.
    3. Aerate your lawn if you need to. While it’s possible to grow grass seed on hard dirt, it’s much easier for the roots to push through soil that is not compacted.
    4. Dethatch your lawn to promote good seed-to-soil contact, especially if you will be overseeding your lawn. It also helps deter pests and lawn diseases.
  3. Use a broadcast spreader or drop spreader to spread the grass seed evenly.
    1. First, spread half of the seeds across your lawn from north to south.
    2. Then, spread the remaining half from east to west. This will ensure even coverage.
  4. Rake in the seeds lightly to promote good seed-to-soil contact.
  5. Apply starter fertilizer evenly over the seeded area.

If you want a more in-depth, step-by-step guide, you can read our article on How to Plant Grass Seed.

Here are some tips to keep in mind when you plant your grass seed:

  • Check the weather conditions before you plant your grass. You want to avoid planting if heavy rain is predicted in the coming days as it can lead to your seeds washing away, getting disease, or even rotting. You also want to avoid windy days for an easier time spreading the seeds evenly.
  • Consider hand-pulling if you have to deal with weeds. If you use herbicide, be prepared to wait a month before planting your seeds. Pre-emergent herbicides are especially problematic for new turf as they can prevent the seeds from sprouting.

How do you care for new grass?

Your new grass will need a lot more TLC from you to grow into a healthy lawn. Here’s how to care for your newly planted grass seed and seedlings:

  • Water your new grass frequently but not deeply to keep it moist but not soggy.
  • Don’t mow until your lawn is 3 to 4 inches tall. It may take as little as a few weeks to a few months before you can break out the lawn mower.
  • Avoid foot traffic on your new lawn. Keep pets and children off the grass and prevent your furry friends from relieving themselves in the newly-seeded areas.
  • Add mulch, straw, or peat moss to the newly seeded areas to help prevent evaporation. It also will protect your seeds from birds and other pests.

FAQ on the best time to plant grass seed

Can you lay down grass seeds in the winter?

Yes, you can lay down grass seeds in the winter. This practice is called dormant seeding, and some farmers and gardeners do this to give their cool-season grass seeds a head start in the spring. Done in late fall up to early winter, dormant seeding can help reduce competition for new grass.

However, don’t expect your grass seed to sprout until the coming spring. This method is not ideal if you want to grow a lawn within the next few weeks.

How long will it take for my grass to germinate?

Your grass can take as little as five days or as long as 30 days to germinate depending on the type of grass. You can consult this table to find out how long you’ll have to wait for each grass type to sprout:

Grass Type    Germination Rate
Bahiagrass7 – 21 days
Bermudagrass10 – 30 days
Centipedegrass14 – 21 days
Fine Fescue7 – 14 days
Kentucky Bluegrass14 – 30 days
Perennial Ryegrass5 – 10 days
Tall Fescue10 – 14 days
Zoysiagrass14 – 21 days

If you want turf that grows fast, then consider planting perennial ryegrass, fine fescue, and bahiagrass.

How do you overseed a lawn?

The process of overseeding your lawn is quite similar to that of planting grass seed. After all, the end process is growing new grass from seed. The only difference is that you’re just spreading seed on bare spots on an existing lawn. Here’s how to overseed your lawn:

  1. Mow your grass very short, about 1 ½ to 2 inches.
  2. Prepare your soil by dethatching, aerating, and fertilizing if needed.
  3. Spread the seed.
  4. Water your lawn and keep the new grass moist.

Hire a Pro to Grow a New Lawn

Are you ready to grow a green lawn? Be sure to plant your grass seeds at the right time and you’ll be on the right track. However, that’s only the first step toward a lush lawn. You also have to take good care of it, especially during the first few months of your new lawn’s life. Neglect – especially when it comes to watering – can kill your grass before it has even sprouted.

If you don’t have the time and energy to spend on taking care of a new lawn – or even an established lawn, for that matter – then consider hiring a professional lawn care service. Don’t know where to hire a pro? Lawn Love can connect you with lawn care pros in your area who can do the seeding, mowing, and general lawn maintenance for you.

Main Photo Credit: schulzie | Canva Pro | License

Janine Caayao

Janine Caayao has always been fascinated with growing plants, from fruits and veggies to bonsai trees and orchids. Now, she’s interested in urban gardening with her family. She loves finding new tips and tricks to keep their plants thriving.