When is the Best Time to Plant Grass Seed?

person planting grass seeds

Sometimes the grass is greener on the other side of the fence because yours has bare spots and thinning turf. Don’t get green with envy! Seeding your lawn with new grass isn’t difficult, but your success hinges on proper timing. This guide can help you figure out the best time to plant grass seed in your area.

The best time to plant your grass heavily depends on the type of grass you’re trying to grow, and that’s usually dictated by where you live. Do you live in a cool-season grass area, a warm-season grass area, or the transition zone, where both types of grass can thrive? Check out this map to see what type of grass seed is typically grown in your region.

A picture showing the distribution of various grasses
Credit: Juan Rodriguez

When to Plant Cool-Season Grass

If you live in the Midwest or further north, you most likely have cool-season turf in your yard. Since cool-season grass grows most vigorously in the fall and spring, the best time to plant cool-season grass is late summer or early fall. Your window of opportunity changes depending on how close you are to the transition zone:

  • Above the transition zone, homeowners can seed their lawns as early as August 15th but no later than October 1st.
  • If you’re closer to or are in the transition zone, you should wait a bit longer before seeding; you can seed from around Labor Day to late October.
A picture showing growth of cool season grass round the year
Credit: Juan Rodriguez

You should always plan around the first frost date when planting cool-season grass. Aim to seed no later than 45 days before the estimated date of the first frost. Why? Cool-season grass seeds sprout best when the soil is around 50 to 60 degrees Fahrenheit (when the air temperature is about 60 to 75 degrees), but they need time to establish before winter sets in. If you plant too late in the fall, your grass might not survive the harsh cold – if the seeds even sprout at all.

The second-best time to plant cool-season turf is in the spring, but it’s not as good because your grass will have to compete with weeds or will be more vulnerable to lawn disease due to the wetter soil. Also, your grass may not have enough time to establish itself before the heat of summer stunts its growth. If you want to plant cool-season grass in the spring, aim for April 1st to May 15th, once the last frost events have passed.

When to Plant Warm-Season Grass

Homeowners in southern states – as well as some in the transition zone – typically have warm-season grass growing on their lawns. Because warm-season turf grows best during the summer, you want to plant it during late spring or early summer. While those are the best times to plant warm-season grass, you can also plant it in early spring or late fall if your area has consistent temperatures all year round (meaning mild winters).

Credit: Juan Rodriguez

Those that have more variable temperatures throughout the year should plant their warm-season grass seeds as soon as all danger of frost has passed. You want to take advantage of the warm soil and early seasonal rains to give your grass a good head start before it gets too hot. You should finish planting 90 days before the predicted first frost date.

Warm-season grass germinates best when the soil temperature is in the 65 to 70-degree range. That translates to an air temperature of about 80 degrees Fahrenheit in the daytime. 

Homeowners living near or in the transition zone may need to wait until May to plant their warm-season grass because of the risk of frost. 

Tips for Planting Grass Seeds

Knowing the best time to plant grass is an important part of successfully growing new turf, but it’s not the only thing to keep in mind. Weather and lawn prep also help a lot. Here are some tips for planting grass seeds:

Check Weather Conditions

You want to avoid planting grass seeds before heavy rainfall because they might wash away. So, you should hold off on seeding your lawn if the weather forecast predicts a coming storm.

While wet soil isn’t a problem, muddy soil is. Planting grass when there’s too much soil moisture is just setting yourself up for disaster. Your new lawn might have to contend with fungal diseases early in its life if you plant it in muddy soil.

You should also avoid planting grass seeds when it’s windy outside so the seeds don’t get blown away. 

Stop Using Herbicide

If you plan to plant grass, you should mind your herbicide use. In most cases, you should stop using herbicides at least a month before you plant your grass seeds. However, some herbicides require a longer period of time between the last use and planting. Homeowners that treated their lawns for crabgrass have to wait an average of four months before seeding their lawns.

Level Your Lawn

While planting grass on a slope isn’t impossible, it’s certainly more difficult. If you don’t want the extra trouble, you should level your lawn before planting. Fill in valleys with a mix of sand, topsoil, and compost. You can use a rake to level the soil. Any rocks and debris should be removed, too.

Aerate Your Lawn

The root system of grass seedlings isn’t strong enough to break through tough, compacted soil. Lawn aeration can take care of your soil compaction problems. It also helps control weeds and mitigates drought stress, both of which are dangerous for new seedlings. 

If you want to save money, you can aerate your lawn DIY with garden forks or aerator shoes instead of hiring a lawn care company or renting a core aerator machine. 

Test Your Soil

Instead of guessing what nutrients and amendments your lawn needs, you can conduct a soil test. The soil test results will tell you exactly what’s up with your soil and help you figure out how to correct any problems.

Use a Starter Fertilizer

There are special fertilizers formulated for growing grass, which can give your new turf the boost it needs to grow vigorously. Check if your state or county has any restrictions on fertilizer, though, and be careful not to over-fertilize. Too much starter fertilizer can backfire on you and harm your growing turf instead.

Spread Seeds Evenly

Nobody wants a patchy, uneven lawn. To make sure your grass seeds are spread evenly, you can use a seed or fertilizer spreader. Just make sure it’s not windy out when you do it.

How to Care for New Grass

Whether you’re patching up an existing lawn or seeding a new one, there are a few precautions you must take before you can confidently say your newly-seeded grass is ready to enjoy. Like any growing plant, your grass seedlings are delicate and need more TLC than an established lawn. Here are some things to keep in mind as your new grass is growing:

Water Regularly

Your newly-planted grass will need a lot of water to grow fast. However, you should be careful not to overwater. A light sprinkling every morning should be enough, but you should water again in the afternoon if the soil has dried out. Do this until you’re sure all of your seeds have germinated. See our article on how often to water grass seed to learn how you should adjust your watering schedule as the seeds begin to sprout and grow.

Hold Your Mowers

Wait at least 2 months before mowing your new turf. Most turfgrasses should be about 3 inches tall before their first mow. You can read our article about planting grass for a more comprehensive list of what length grasses should be before being mowed for the first time.

Keep in mind that grass planted in shaded areas grows slower, so you will have to wait a longer time before you can mow it.

Don’t Disturb the Grass

While your grass is growing, keep foot traffic to a minimum. That means no stepping on the grass and no playtime in the yard for at least a month. And you definitely don’t want your dog or cat using the bathroom on brand-new grass. 

FAQs About the Best Time to Plant Grass

What grass germinates the fastest?

Annual and perennial ryegrass seeds can germinate in as little as 5 days. Bermudagrass and buffalograss are tied for second place, which can germinate in as little as a week.

Purchase ryegrass seeds here:

Outsidepride Perennial Ryegrass Seed (5 lbs.)
Eretz ProTurf Perennial Ryegrass Fine Lawn Seed (choose your size)

Purchase Bermudagrass seeds here:

Pennington Bermudagrass Bare Spot (5 lb. bag)
Pennington Smart Seed Bermudagrass Mix (8.75-lb. bag)
Scotts Turf Builder Bermudagrass (10-lb. bag)
Hancock Seed Co. Bermudagrass (50-lb. bag)

Purchase buffalograss seeds here:

Everwilde Farms Buffalograss Seeds (1 lb. of seeds)
Buffalograss seed (primed) (5-lb. bag)

Can you plant grass seeds in March?

For most parts of the country, March is too early in the year to plant grass. It’s usually too cold, and there’s a risk of frost. However, you might be able to plant grass seeds in March if you live in the far South.

When should you overseed your warm-season lawn for the winter?

Homeowners with warm-season lawns might want to overseed with cool-season grass each year so they can have a green lawn in the winter. If you’d like to overseed for winter color, you should plant the cool-season grass in the fall.

Get Yourself a New, Green Lawn

Having a lush lawn isn’t that hard, but it does take some work and planning. Instead of worrying yourself silly, why not hire someone who knows more about growing grass than you can learn from one guide? 

Lawn care pros in your area have the knowledge and tools to give you a beautiful lawn while you sit back and relax. Contact a lawn care company through LawnStarter today to get started on the lawn of your dreams!

LawnStarter participates in the Amazon Services LLC Associates Program, an affiliate advertising program. LawnStarter may earn revenue from products promoted in this article.

Main Image Credit: schulzie / Canva Pro / License

Janine Caayao

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.