It might seem like an easy task, but learning how to plant grass seed correctly is essential for growing a thick, healthy lawn. With just a little know-how, you can bring to life a beautiful expanse of inviting green grass. We break down how to grow a lawn from grass seed into six simple steps How to grow lawn that is lush and full of grass. Checklist to grow a weed-free lawn. Growing a lawn without weeds is a dream for many homeowners. This checklist will help you keep the weeds away from your lawn while maintaining healthy grass and teach you how to make St Augustine grass thicker.
How to plant grass seed: A simple guide to success
Lawns are everywhere. Some are highly tended; others, not so much. My own lawn is a mixed planting of three types of turf grass (Kentucky blue, fescue, and perennial rye grass), clover, violets, ground ivy, and various other “weeds”, which is exactly how I like it (and so do the resident honey bees and bumble bees!). Regardless of how perfectionistic you are about your lawn, at one point or another, you’ll find yourself needing to plant grass seed. Whether it’s to fill in a bare spot left behind by Fido or a wayward snowplow, or to install a brand-new lawn after a construction project, learning how to plant grass seed is a necessity for most homeowners. This article offers a simple guide to success, no matter the reason for your reseeding efforts.
There are many different types of lawn grasses. Be sure to choose varieties that are suited to your climate.
Start with the best type of grass for your climate
As a professional horticulturist and a former landscaper, I’ve seeded dozens of brand-new lawns over the years, and I’ve over-seeded bare spots in hundreds more. No matter how large or how small your job is, success always starts with selecting the best grass seed for your region. Different grass species thrive in different climates. There are cool-season grasses and warm-season grasses. The label of the package will tell you which grass varieties are included. It will also tell you whether or not there is a starter fertilizer included. Do not choose a blend that includes weed control products. They could harm young seedlings.
Which grass seed is best for your yard also depends on the amount of sunlight it receives. I suggest contacting a local garden center or feed store and speaking with them about the best options for your region. There are also some useful online maps with all the information you’ll need to choose the appropriate grass species for your growing conditions if you live in the US.
Some brands of grass seed come blended with a “filler” product intended to help you distribute the seed evenly and to act as a protective covering. I personally avoid these products because they are more costly than purchasing a bag of high-quality plain seed and they don’t cover as large of an area.
Preparing the ground for planting
After selecting and purchasing the seed, it’s time to prepare the soil for the planting process. This is a very important step in knowing how to plant grass seed successfully. The tender roots of young grass plants will not grow well in compacted soils so it’s essential that this step be done properly. Here are instructions for prepping the ground to overseed bare spots in an established lawn and instructions on how to prepare for planting grass seed in a large bare area.
Preparation for seeding a bare spot in the lawn: Begin by using a cultivator to remove the dead grass. If it’s a small spot, use a hand cultivator. If it’s a larger spot, use a diamond hoe or warren hoe. Then, dig up the area down to a depth of two or three inches with a shovel or trowel. Loosen the soil and break up any clumps.
To repair a “doggie spot” in your lawn, start by removing the dead grass.
Preparation for planting grass seed in a large bare area: If you want to know how to plant grass seed in larger areas successfully, begin by loosening the top three to five inches of soil. Use a rototiller for the job if it’s a very large lawn area. Use a shovel or hoe if it’s an area that’s just a few square feet.
For a smaller area, break up the soil using a warren hoe or a shovel. Larger areas may require a rototiller.
Whether the area is small or large, after loosening the soil, it’s time to rake it smooth. Use a bow rake or a seeding rake to further break up any soil clods and rake the soil out into fine particles and a smooth finish. Use the tines of the rake to smash any large clumps of dirt if necessary.
After loosening the soil, rake it out smoothly and break up any clumps.
The final step of site preparation for planting grass seed is to water the area well. Putting seed down on damp soil encourages speedy germination and provides immediate moisture to emerging roots.
Wetting the area before planting is an important step in the process.
How to plant grass seed
For small areas, use your hand to distribute the seed, flinging it out over the area. For large areas, use a walk-behind broadcast spreader or a hand-held hopper spreader to disperse the seed. It’s all too easy to put down too much seed, or conversely, not enough seed. When you’re finished, the grass seeds should be evenly spread over the soil surface. They should be about one-quarter to one-half inch apart (obviously no one expects you to actually measure – just eyeball it). If you sow grass seed too thickly, the plants will outcompete each other and their growth will suffer. If you don’t sow them thickly enough, weeds may move in.
In smaller areas, grass seed can be spread by hand. For large areas, use a mechanical spreader.
How to ensure good coverage
Sometimes it’s challenging to ensure ample coverage of grass seedlings. If you are using a drop spreader, I suggest distributing the seeds in one direction and then making a second pass in the perpendicular direction. This two-directional overseeding promotes more even grass seed germination and distribution. If you are spreading the seed by hand, it’s a bit easier to eye, but dropping the seeds from different angles helps.
What to put on top of newly planted grass seed
After the seeds are sown, cover them immediately to protect them from birds, keep them moist, and prevent them from washing away in a heavy rain. There are several different mulches you can use for the job. In my experience, straw (not hay, which can be filled with weed seeds), screened compost, or mushroom soil are prime choices. These products also act as soil amendments when they break down and can improve your soil’s fertility and structure. All three of these options are available from your local garden store or landscape supply center. Erosion mats are another option. They can easily be unrolled over the area with little mess and are biodegradable, though they’re also a good bit more expensive than the previous choices. Peat moss is not a good idea because it can repel water once it has dried out.
No matter what you choose to use to cover grass seed, more is definitely not better. One-quarter of an inch is about as thick as you should go. Compost and mushroom soil are great for covering fall-seeded lawns. Their dark color absorbs the sun’s heat and keeps the soil warm all night long. This speeds germination and encourages rapid lawn establishment prior to winter’s arrival.
After spreading the seed, cover the area with a mulch of straw, fine compost, or mushroom soil.
How long does it take for grass seed to germinate
Some varieties of turfgrass take longer to germinate than others. For example, perennial rye grass germinates in as little as 3 to 5 days, fescues take more like 10 days, Kentucky bluegrass takes 2 to 3 weeks, and warm-season grasses like centipede, Bermuda, and zoysia grasses can take over a month. If your grass seed is a mixture of varieties, know that not all of them will germinate at the same time. To encourage good germination and a healthy start no matter which type of grass seed you planted, it’s critical that you keep the seeded area and the young plants well-watered until they are established. See the section below on watering for more info on how and when to water new grass.
Water newly planted grass in well and keep it watered until it’s established.
Planting grass seed in fall
In many climates, the best time to plant grass seed is in the autumn. The still-warm soil of late August, September, October, or November encourages optimum root growth, while the cooling air temperatures discourage excessive top growth. This is perfect for establishing lawn grasses and promoting extensive root growth. It also makes the turf more resistant to drought and better able to access nutrients in the soil. In addition, in most regions, fall also brings increased amounts of rainfall. This means you won’t have to lug out the hose and sprinkler as often.
It’s time to plant grass seed in the fall when nighttime temperatures drop down to about 60 degrees F. Keep an eye on the forecast. Opt for sowing grass seed when there’s a day or two of rain predicted.
Planting grass seed in spring
Spring is another great time to seed the lawn. It’s particularly good if you live where springs are long and cool. For spring planting, it’s absolutely essential that you continue to regularly water the seed and the sprouted grass through the remainder of the spring, summer, and well into the fall. Establishment failures are often connected to improper watering. Early summer is another possible time, but you’ll need to water more often.
How often to water grass seed after planting
Water newly planted grass seed daily if the weather is over 80 degrees F. Every other day is a good watering schedule if temperatures are cooler. Prior to germination, wet the top inch or so of soil. But, once the grass seed germinates and begins to grow, reduce the frequency of irrigation but water more deeply. Once your new grass is about two inches tall, reduce your watering schedule to once or twice a week, but water until the ground is wet down to a depth of about three inches.
Once grass is fully established, stop irrigation all together, unless there’s a prolonged period of drought. When it comes to watering established lawns, it’s always better to water less frequently but very deeply. Always water lawn in the morning, if possible, to reduce the chance of fungal disease issues.
Young grass plants can be mowed when they are 3 inches tall.
When is it safe to mow new grass?
Mow new grass when it reaches a height of about 3 inches. Mow high through the first growing season (3 to 4 inches). Make sure your mower blades are sharp (here’s my favorite sharpening tool) so they cut the grass cleanly, rather than tearing it which can create an entryway for disease.
When to fertilize new grass
When learning how to plant grass seed, many people think you should add fertilizer at planting time. This is not a good practice however, because fertilizers (especially salt-based synthetic lawn fertilizers) can burn tender young grass roots. Instead, top-dress the lawn with compost (here’s how) or use an organic granular lawn fertilizer instead of a synthetic brand. You can start to fertilize new lawns after you’ve mowed the grass 6 times.
Now that you know how to plant grass seed, it’s easy to see how doing it right can make all the difference. Follow the steps outlined above and you’ll have a healthy, thriving lawn instead of one that’s struggling.
For more on growing a beautiful landscape, please visit the following articles:
What do you suggest for slugs. I have huge issues worth them this summer. I have switched to a battery lawnmower vs. gas. Would the gas have killed them in the past? Anyway I planted triple rye seed this fall and found hundreds of them.I have been going out at night and scooping them up with a spoon and dumping them in soapy water but I never beat them just control them somewhat. Thanks kindly for any advice.
Hi Barb. Here’s an article on our site that discusses what to do about slugs: https://savvygardening.com/how-to-get-rid-of-slugs-in-the-garden-organically/
Annwen mazetti says
I see you don’t compost the soil. Just want to double check that that is ok – do I really only need to topdres?
If your home is new construction then I would suggest working compost into the area. But, if you have an existing lawn, there’s really no absolute need. It doesn’t hurt to add compost prior to planting, though.
Amy Conley says
What do you suggest for moles that are destroying my yard and therefore my grass? It needs to be safe around pets.
How to Plant Grass Seed in Six Steps
If your spouse keeps telling you the grass is greener on the other side of the fence, you might want to tackle the naked-earth lawn chore you’ve been dodging. We’ll show you how to plant grass seed in six steps. You’ll complete one of the most satisfying outdoor tasks a homeowner can accomplish (and maybe save your relationship).
Here’s how to plant grass seed in six simple steps:
Step 1: Remove the Existing Grass
Is your lawn happily surviving? If your grass is good, but could be better, you could overseed to plump up the existing lawn. For bare spots, use garden tools to roughen up the soil first. Then spread the grass seed over to fill in the bare patches.
If your yard is where feisty weeds go to party and half of your lawn lies naked, you should plan to renovate — remove the old vegetation. New baby grass seedlings cannot compete with that mess. If you’re starting from scratch with a new home build, and establishing a new lawn, you can skip to Step 2.
There are two ways to clean your lawn’s slate:
- Use a nonselective broad-spectrum herbicide. Follow label instructions carefully and don’t spray on a windy day.
- Use a sod-cutter, available at most rental companies. Mark your sprinkler heads before operating the cutter to avoid accidents.
Once the weeds and old sod are removed, loosen the soil bed so the new grass seeds’ roots can easily grow through. You can use hand tools (and your toughest friends), a tiller, or core aerator. You can find tillers and aerators at rental companies, as well.
Fill low spots in your yard using a half-and-half mixture of sand and topsoil. If necessary, grade your yard to keep rain or water flowing away from your home.
Step 2: Do a Soil Test, then Add Amendments
Once you have renovated your lawn – exposed and leveled the planting surface – you’ll need to test your soil for the best grass germination and growth. Test the soil as soon as you can. There can be a wait of up to two weeks for results and you could miss your ideal planting window.
At a minimum, you should test for pH. This is a measurement of the acidity or alkalinity of your soil. Most grasses like slightly acidic soil, with a pH of 6.2 to 7.
A simple moisture and pH tester can be found for $10. For about $20, you could test for the major nutrients in your soil. Your results will show the N, P, and K: nitrogen, phosphorus, and potash.
The best soil tests include major and minor nutrients. Your state Extension service and private labs offer these services. Keep in mind your local Extension office can also provide great information and insight that private labs can’t, and usually at a lower cost.
Here are four very good soil tests you can buy on Amazon.
The test results should give you a plan and shopping list for your local garden shop. Follow application instructions carefully and add soil amendments to restore what it lacks. Again, use a tiller or hand tools to work the amendments in to a depth of 1-4 inches.
Step 3: Choose the Best Seed for Your Region
Your local seed expert will always give you the best advice when choosing your seed. Local Extension offices, seed stores, and agricultural suppliers are experienced and understand the microclimates of your area.
In northern states, select cool-season grass, which grows best when temperatures are 60-75 degrees Fahrenheit. Cool-season grasses thrive in the late spring and early fall months in the northern two-thirds of the United States.
People living in Southern states should select a warm-season grass seed. Warm-season grasses thrive from late spring through summer.
Between the North and South is the transition zone where summers are hot and winters are cold. You’ll either need to find the most cold-tolerant warm-season grass available, or the most heat-tolerant cool-season grass.
Best Cool-Season Grasses for Northern States
- Bentgrass is a standard grass for golf course putting greens. Colonial Bentgrass is for home lawns and likes a low mow.
- Kentucky bluegrass is a classic choice for Northern lawns. It likes full sun and isn’t shade tolerant.
- Fine Fescue is a perennial bunchgrass and stands up in poorly drained areas.
- Tall fescue mix puts down deep roots and is drought tolerant.
- Creeping fescue is slow to germinate and spread, but tolerates shade, and is good for large lawns.
- Ryegrass (annual) can be used for a quick shot of green. The perennial ryegrass variety is best for high traffic and playgrounds.
Best Warm-Season Grasses for Southern States
- Bahiagrass has a coarse texture, is heat/drought tolerant, and is best for low traffic lawns.
- Bermudagrass is hardy and stands up to heavy traffic, but it’s high maintenance.
- Buffalograss is the only variety native to North America, highly drought tolerant, and needs little care.
- Centipedegrass grows slowly but has very low maintenance once established. In warm climates, it’s non-dormant, so it stays green year-round unless there’s a cold snap.
- Zoysiagrass is a slow grower, but one of the most cold-tolerant varieties of warm-season grasses.
- St. Augustinegrass is sold as sod, as its seedheads are sterile.
Best Grasses for Transition Zone States
The transition zone is a blend of temperature highs and lows, humidity, summer deluges, and drought.
- Kentucky bluegrass
- Perennial ryegrass
- Tall fescue
Single Variety, Blend, or Grass Seed Mix?
In addition to high-quality grass seed to match your climate, you also need to consider your lawn’s unique properties.
- Is it in full sun, shade, or a mix? A shade mix is great for dense shade.
- How much moisture will it get?
- Is the area heavily trafficked?
- How much time and effort do you want to spend maintaining the lawn?
Knowing your terrain will help you home in on the formulation of seed you want. Seeds are sold as pure seeds of one variety, blends (multiple types of the same variety), and mixtures (seed blends of different varieties).
Pure seed will give you a unified look. Blends will be less uniform, but one variety may cover up for the weaknesses of another. Grass seed mixtures provide the most biologically diverse lawn: the grass plants won’t look identical, but your lawn has a better chance of surviving diseases and droughts.
Step 4: Best Time to Plant Grass Seed
For cool season grass seeds, either spring or fall are the preferred times, since these northern varieties of grass prefer warm soil and cool air.
In the South, warm-season grasses can be planted from late spring to mid-summer. Wait until the last chance of a late frost has passed, and the daytime temperature is in the 80s.
One of the biggest keys to success is picking a high-quality seed that is right for your climate.
Federal Seed Act Ensures Proper Labeling
When it comes to selecting seeds, the Federal Seed Act requires seed sellers to provide consumers with valuable information on the seed’s label.
Under the law, the label must tell you:
- The name of the grass variety (or varieties).
- Its purity, that is, the weight by percentage of each type of seed.
- Germination percentage. The percentage of the seeds that you can expect to germinate. This is not a number the seed companies can fudge. The federal government expects seed producers to run regular germination tests and keep careful records.
- Weed seed percentage. Look for a seed that has less than 0.5 percent weeds.
Pure Grass Seed or Fertilizer/Mulch Mix?
You have one final decision to make. Are you going to purchase a seed that incorporates fertilizer and mulch, or purchase fertilizer and mulch separately? The all-in-one products are more expensive but are convenient.
Measure your lawn area in square feet, and purchase enough seed to cover that area. Usually, seed bags are marked as the number of pounds needed per 1,000 square feet. If possible, buy a little more than needed in case you want to reseed some bare spots.
If you are fertilizing separately, broadcast the fertilizer according to the manufacturer’s instructions.
Plant your Grass Seed and Fertilizer
To plant grass seed in small areas, hand-seeding is fine. For larger areas, seeders and spreaders provide more precise coverage. You can find hand-cranked spreaders, chest-mounted, or push-from-behind seeders. Drop seeders drop seeds directly below the unit. There are more expensive commercial seeding options as well.
Follow the instructions on the seed bag. If the seeder’s lowest setting seems too generous with the seed, thin it out with sand or vermiculite.
- For large lawns, fill the push spreader with seed.
- Spread half of the recommended seed north to south.
- On the second pass, spread east and west for even coverage.
- Rake the top ⅛-inch of the seeded surface lightly. Using the back of a leaf rake side-to-side makes this an easy job.
- If you have access to one, roll an empty lawn roller to improve germination.
“We call it ‘the seed-soil contact,’” said University of Illinois Extension office educator Richard Hentschel. “You want good seed-soil contact. If the seed and soil are not in intimate contact, the little root radicle may die out before it hits the soil.” The radicle is the first root to emerge from a seed.
If you have hilly areas, seeds will tend to wash away to a low point. One potential solution is hydroseeding: broadcasting seeds that are suspended in a fertilizer-mulch slurry. Professional landscapers often offer hydroseeding services, and there are some hose-end sprayers for the do-it-yourselfers.
Lawn-Starting Fertilizer: Watch the Phosphorus
You need to find out if your state restricts using fertilizers containing phosphorus. Most laws carve out an exception and allow limited application of phosphorus on new lawns, but turf experts say to let your soil test be your guide. If it says that your soil lacks phosphorus, then it’s acceptable.
Step 5: Aqua and Attention
Keep a careful eye on your new grass seeds. They only get one shot to germinate, so what you do now is critical. That means water. Keep in mind that different grass plants germinate at different times, so if you have a mixture of grass seeds, you’ll need to keep watering them until the slowest-germinating species emerges.
- Keep the top layer of soil moist (but not soggy) down to 1/2 inch. (Too much water is as bad as too little, and overly vigorous watering could wash the seeds away.)
- Water at least once a day in the morning and perhaps again in the afternoon if the sun and wind have dried out the soil.
A misting attachment on your hose can cut down on the amount of force you use. Part of your lawn may be shadier, part may have more porous soil, or part may be sloped. Adjust your watering according to your lawn’s needs.
Grass Seed Germination Rates, by Grass Type
- Bahiagrass seed: 10-28 days
- Bermudagrass seed: 7-28 days
- Kentucky Bluegrass seed: 14-21 days.
- Buffalograss seed: 7-10 days.
- Centipede grass seed: 14-28 weeks.
- Fescue grass seed: 10-14 days.
- Annual ryegrass seed, perennial ryegrass seed: 5-10 days.
- St. Augustinegrass: Rarely grown from seed, propagated by plugs and sod.
- Zoysia grass seed: 14-21 days.
Even if you planted just one turfgrass variety, the grass seeds won’t all pop up at once. Some will be buried a bit deeper or have a different rate of water absorption. Stay with your watering regimen until you’re sure the seeds have germinated.
Keep foot traffic to a minimum. You could consider putting up “Please keep off the new grass” signs to discourage accidental trampling by your kids and neighbors (and their dogs).
Step 6: When to Give your New Lawn its First Mow
Hooray! Your new lawn is green and it’s growing well.
Here’s how tall your grass should be before you mow for the first time:
- Bahiagrass: 2-2 ½ inches
- Bentgrass: 1 inch
- Bermuda: 1½-2 inches
- Bluegrass: 2-2½ inches
- Buffalograss: 2-3 inche
- Centipede: 1½-2 inches
- Fescue: 2-3 inches
- Perennial Ryegrass: 2-3 inches.
- Zoysia: 1-2 inches
Treat your New Grass like a Baby
Take advice from the ‘70s band, The Eagles. Slow down and take it easy the first few times you mow your new turfgrass. The roots won’t be long or well-established, so it will be easy to accidentally rip up the young plants.
Here are a few tips to ensure a successful first mow:
- Sharpen the mower’s blade so you cut, not tear, the tender plants.
- Start the mower off the lawn and minimize the number of turns you make with the mower.
- Don’t remove more than a third of the grass blade in one mow.
After the first mow, cut back on frequent shallow watering, and switch to watering a couple of times a week, deeply. Water six or eight inches deep to encourage your new lawn to root deeply. Once established the lawn will start spreading to cover any gaps.
After eight weeks, your lawn should be well-established. Hit it with a little more fertilizer to encourage deep roots, and take down your “Please keep off the new grass” signs; your new lawn is ready for fun.
It’s unlikely that grass seeds will grow on top of flat, bare soil. The seeds may germinate but the roots won’t be strong enough to penetrate the soil. It’s best to rough up the soil before sowing for the best seed-to-soil contact.
Don’t cover grass seed with topsoil. The seed needs light to germinate. To protect the seed from birds and washing away, use straw (weed-free) or an erosion-control blanket.
Expect to see tiny grass blades in 10-14 days. Other varieties of seed may take up to 30 days.
DIY or LSE (Let Someone Else)?
Some homeowners and renters love being weekend warriors, but some of the rest of us prefer anything else.
If you’re like me, and you would rather reap the rewards of great grass someone else sowed and mowed, consider hiring a lawn care pro. Give them a call early so they can begin testing and sowing seeds at the proper planting time for your area.
* Editorial Note: LawnStarter participates in the Amazon Services LLC Associates Program, an affiliate advertising program. LawnStarter may earn revenue from products promoted in this article.
LawnStarter writer Penny Warner updated this article.
Daniel Ray is LawnStarter.com’s former editor in chief. He is an award-winning writer and editor who previously was editor in chief of the personal finance websites Bankrate.com and CreditCards.com, but with 30 years of gardening experience, he’s well qualified to help consumers grow a different kind of green.
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How To Grow A Grass Lawn Without Weeds
Growing a lawn without weeds is a dream for many homeowners. While it’s probably unrealistic to have a lawn 100% free of weeds, you can aim to grow a thick, healthy stand of grass. That’s actually the easiest way to give weeds the brushoff: grow turf that’s so thick and strong that weeds can’t find an inch to take root. Follow this checklist to grow your healthiest grass ever.
Grow the Right Grass
Different grasses grow in different areas of the country. Warm-season grasses are usually grown in warmer, more southerly regions. Types include Bahiagrass, Bermudagrass, St. Augustinegrass and Zoysiagrass. Cool-season grasses are typically grown in cooler, more northerly regions. Types include Fescue, Kentucky Bluegrass and Ryegrass. Check with your local Cooperative Extension System office to learn which types of grass grow best in your area.
Start by cutting grass with a sharp mower blade that cuts grass cleanly, without tearing or shredding. Proper mowing height depends on grass type. Vary your mowing pattern to avoid creating ruts in the lawn. Avoid mowing when soil is wet, or you risk tearing up grass and soil.
Provide adequate moisture to grass, especially during episodes of drought or high temperatures. Provide deep, infrequent irrigation, which promotes healthy, deeper roots. Learn about lawn irrigation basics and how much grass actually needs.
Before you start a fertilizer program, do a soil test so you know you’re applying the correct blend of nutrients. In some parts of the country, soils may be acidic or alkaline and require additions of iron, magnesium or lime. Also, different types of grass need to be fertilized at different times of the year. Check with your local Cooperative Extension System office for help developing the right fertilizer program for your lawn.
Scout for Problems
Like any landscape planting, lawns can suffer from a variety of problems. Weeds, bare spots, insects and diseases can weaken and, if left untreated, even destroy a healthy lawn. Keep an eye out for problems in your lawn.
- Deal with weeds when you first see them, because one weed leads to many more. Learn about the types of lawn weed killers and when to use each. Discover why fall weed control is key and how to do it successfully.
- When a bare spot appears, figure out the cause and deal with it. Open soil extends an invitation to weeds, so repair bare spots as quickly as possible.
- Scout for insect problems. Some of the signs to look for are skunks digging up lawn or flocks of birds feeding on turf. White Grubs are a common lawn pest. Discover the basics of dealing with Grubs.
Aerate and Dethatch
Compacted soils don’t allow air and water to reach grass roots, which results in unhealthy grass.
Aerating helps relieve soil compaction.
When thatch builds up in a lawn, it can prevent water and fertilizer from reaching soil and provide refuge for insects.