The Best Time to Plant Grass Seed

It doesn’t take a rocket scientist to figure out how to grow a beautiful lawn, but it does require some careful planning. 

Growing a verdant, healthy lawn starts with the right timing. Once you know the best time to plant grass seed, you’ll be able to maximize your time so you have to do as little work as possible for a healthy lawn.

Don’t worry – picking the right time doesn’t require fancy calculations or apps on your phone. Instead, consider these tips to find the best time to plant grass seed depending on your climate, grass type, and goals. 

Grass Climates

Figuring out the best time to plant grass seed starts with your grass type. And choosing the right grass type depends heavily on your climate. 

If you live in the northeast, you’ll want to plant cool-season grass, while in the south, warm-season grasses are best. If you live in the midwest, you will generally do best with cool-season grass, but this can vary depending on your humidity levels. 

In the deep south and Gulf Coast regions, you’re generally going to want to plant a warm-season grass that likes a bit more humidity, such as centipede grass. For the Pacific Northwest, you will want to plant ryegrass that is resistant to disease, as this region gets a higher annual rainfall than is average. 

Essentially, you need to make sure the temperatures are ideal for the certain type of grass you are growing. Plant warm-season grass seeds during a spring cold snap, and they’ll probably stay dormant until weed seeds overtake the area and make it more difficult for the gears to get established.

The same can happen if you plant a cool-season grass in too-hot temperatures. You need to make sure you plant the grass seed at the right time for its desired climate and at the right depth, too. 

Grass Types

Grass generally falls into two separate categories: cool-season and warm-season grass. These two types have different maintenance and sowing requirements. Paying attention to both can help you achieve good-looking, healthy grass with minimal effort.

Cool Weather Grass

Cool-weather grasses are those that grow best in places where summer temperatures are moderate and winter temperatures dip below freezing. This is because these cultivars tend to require more water, which is often only delivered through heavy snowfall. 

During the warmer summer months, these grasses will lie dormant in the summer and grow best during fall and spring. Therefore, if you’re planting cool-season grass, you’ll want to plant in early fall – before the first frost, but after much of the intense heat of summer has passed. 

The reason for timing this planting as such is that cool-season grasses require much more water than other varieties. By avoiding planting during the hottest days, you won’t have to irrigate as intensely, nor will evaporation rates be quite as high. 

Not sure if the grass you selected is a cool-season grass? Some cool weather grass types include: 

• Kentucky bluegrass
• Perennial ryegrass
• Tall fescue
• Fine fescue 

You will often find these grasses sold in seed mixtures together, but don’t worry – your timeline will be about the same for all of them.

Warm Weather Grass

Warm-weather grass, like Bermuda, Bahia, St. Augustine, and centipede grass, all grow best in climates with hot summers and colder winters. They don’t require as much water and are better suited for holding up to dry spells. They germinate and grow best in temperatures higher than 80 degrees, so you should wait until things heat up to plant. 

Depending on where you live, this could be any time between March and September. Don’t plant right before a heavy rain, though. Not only do these grasses not require as much water, but too much water can wash away the seeds and cause them to rot, too. 

If you aren’t sure whether warm or cool-season grasses are right for you (for example, if you live between climate zones) you might want to pick a cool-weather grass. It will flourish better in a climate that falls between the extremes. You could also try planting a mixture of both in the spring. 

When to Plant Grass Seed

This table below shows you the best time to plant based on the type of grass you are planting. In addition, if you’re unsure of what type of grass you should be planting, the Zones column will help you determine the best pick. Match your hardiness zone from the map above with the grasses in this table.

As a quick summary, most warm-season grasses can be planted in the spring or summer, while cool-season grasses can be planted in the very early spring or fall (fall being the best time). 

Grass Type	When to Plant	Zones
Bahiagrass: Pensacola	Spring / Summer	7 to 11
Bahiagrass: Argentine	Spring / Summer	Lower 8 to 11
Bentgrass	Spring or Fall	4 to 6
Bermuda Grass	March – August	7 to10
Bluegrass	Feb-May Sept – Nov	2 to 6
Carpetgrass	Spring / Summer	Coastal 8-9
Centipede	Spring / Summer	7 to 10
Fescue: Tall & KY-31	Spring or Fall	4 to 7
Fescue: Creeping Red	Spring or Fall	3 to 7
Buffalo Grass – A Native Grass	Spring	5 to 8
Ryegrass: Annual	Fall	All Zones (Seasonal)
Ryegrass: Perennial	Spring or Fall	3-6 Per. 7-10 Overseed
St. Augustine	Spring & April-August	8 to 10
Zoysiagrass	Spring & April-August	lower 5 to 10

Once you determine your ideal grass type and timing, you can started on the actual process of planting. Here’s a quick summary of how to plant grass seed, but I also encourage you to check out our in-depth step-by-step guide to planting grass.

Prepare the Soil 

First things first, make sure you block out some time on the calendar to do some prep work. You might need to remove any obstructions (like sticks or stones) and do some aeration to loosen up the soil. If you already have some lawn growing, you might need to mow it short so you can clearly see the spots that need new seeds.

Before planting, you should also test thes soil to determine whether fertilizers or amendments are needed to get things into tip tops hape. 

Plant the Seed at the Proper Time

Don’t rush to plant but instead, wait until the weather and conditions are ideal. Plant on an overcast but calm day, as this will provide the least disturbance to your seedlings. You can plant by hand or use a mechanical seeder, but whichever you choose, do your best to broadcast sees as evenly as possible. 

After you’ve seeded, cover your seeds with a light layer of soil – no more than a quarter inch. You can fertilize the soil during planting or wait until you’re done, but make sure you take the time to water. You should water immediately after planting as well as daily until seedlings emerge and reach two inches in height. 

Time Other Activities Appropriately, Too

One final tip? If you’re laying down new grass seed, whatever you do, don’t time your planting for before you apply a herbicide. Many herbicides are indiscriminate and can kill your freshly seeded lawn. Instead, wait for at least one month after treating your lawn with chemicals to put down new grass seeds. 

Wait to mow until your new grass ist at least six weeks old. 

When to Expect Results 

When you time your seeding appropriately, your grass seedlings will root well and get established before natural stressors, like heat or cold, set in. When you’ll see results will depend on the type of grass you are growing and what the weather looks like.

For example, some types of cool-season grasses can take three times as long to germinate as others. The same is true of warm-season grasses, too, and if you’re planting a mixture of seed types that germinate at different speeds, it’s anybody’s guess as to when your seeds will germinate! 

Warm-season grasses germinate best when temperatures are hot – the hotter the better. They won’t germinate well at temperatures below 55 degrees. For cool-season grasses, the opposite is true. You’ll want soil that’s cool, but not freezing. Soil that’s very cold and wet can cause seeds to rot and germinate poorly, even if you’re growing cool-season grass. 

You may not be able to control what kind of temperatures hit after you’ve planted your seeds, but you can time your seeding based on weather estimates. You can also maximize your efforts by preparing the area properly and following good tips for planting grass seed. 

Figuring out the best time to plant grass seed is only one piece of the puzzle when it comes to growing a gorgeous lawn. However, it’s an important piece  – and one you can’t ignore. Time your planting correctly, and you’ll be rewarded with a lawn that grows well all season long.