How Much Grass Seed Do You Need Per Square Foot? Application Rate Chart Included

If you are preparing for a reseeding or overseeding project this Fall and you already know what type of grass you want in your yard then all you have to do is follow the seeding rate instructions found on the bag of seeds you’ll be sowing. If however you haven’t decided on the seed yet then you may want to consult the chart below to get an idea of how much seed you will need for your project.

Most grass varieties for both cold season and warm season turf types will require at least 1-5 pounds of seed for every 1000 square-feet of yard space although many cooler season grass types require more and some warm season grass types require less. There are some stark differences in application rates between some grass varieties and coated seeds need to be applied at heavier rates.

Overseeding an existing lawn requires less seed than if you were seeding a new lawn. Overseeding projects will require approximately half of the seed per square foot that you would use on a new yard and if you use a basic drop spreader then you will probably have less waste meaning you will be able to spread slightly less seed and get the same results.

In the northern colder climates Perennial Ryegrass, Kentucky Bluegrass, and Tall Fescues are very commonly found in lawns in America. In the warmer areas to the south Bermudagrass, Zoysia, Centipede, Bahia, and St. Augustine are quite common. We will focus on these grass types for the remainder of this article.

Knowing how much grass seed you need per square foot of your land is possibly the most important factor in growing a thick and healthy lawn. Even with the best watering practices if you don’t use enough seed you’ll likely end up with a patchy lawn with uneven grass coverage.

Before we move on, however, the short answer is:

Depending on where you live, what your climate generally is like, and what the specific variety of grass seed that you use is, you should usually plan on sowing at least 2-3 pounds of grass seed for every 1,000 square feet; generally no more than five pounds although there are some exceptions.

Let’s start with a basic chart to learn more about seeding rates for common residential lawns. This should be your baseline for figuring out how much grass seed you need per square foot in your lawn.

Typical Grass Seed Application Rates

Note #1: The St. Augustine grass type will almost never be seeded in a lawn. Instead it is usually farmed as sod or plugs and installed in a lawn rather than grown from seed.

Note #2: When buying seeds make sure to pay attention to whether the seeds are coated or not. Raw uncoated seeds will be sown at the lower end of the application rates while coated seeds should be sown at the upper end of application rates.

Also, as I mentioned above no matter what grass seed type you are spreading you should always consider using a basic drop spreader over a broadcast for grass seed so that you don’t get grass seed spraying where you don’t want it.

This is a well made classic drop spreader from Scotts that doesn’t cost too much that I recommend over the super cheap handheld broadcast whirley spreaders like the Wizz and the Whirl also from Scotts which are so commonly sold in big box stores.

To learn more about the differences you can see this article I published comparing drop and broadcast spreaders.

Other Factors That Affect How Much Grass Seed You Should Apply

Factor #1: The Type of Grass Seed

Obviously the grass variety will greatly affect the amount of seed you’ll need per square foot but what I’m talking about here doesn’t have anything to do with grass cultivar – I’m talking about the type of seed itself. If it’s a seed only product with no fillers, coatings, inert material, or seed starter blend then you will apply a much smaller amount to your property than otherwise.

In many cases seed bags contain inert material to help the seed establish. Coatings on the seeds are usually meant to help retain moisture and can help with keeping germination rates high. These coatings can also help seeds to germinate faster as they are less likely to dry out on the ground.

Some other bags will contain filler material mixed in so that when you sow the seed it is mixed up in a seed starting mix of soil, peat moss, or some other growing medium. These materials take up space and weight and although they can help ensure seed to soil contact, necessary for germination, they add to the cost and bulk of your seed.

There are calculators online like this one from Lowes that can help you figure out how much grass seed you need and of course you could always eyeball it using the above chart as a guideline — but figuring out the correct amount shouldn’t be particularly difficult either.

Almost all brands of grass seed, whether you buy them online or in a brick and mortar home improvement store, will have an area on the label or the package stating how much is an appropriate amount for your lawn based on the seed variety in the bag and the inert materials in the bag.

This is also more or less the easiest way to determine a good baseline for your appropriate seed spreading rate. You’ll get a concrete number right on the label of whatever brand of grass seed that you buy. That said, there are a few more factors to take into account with seeding a lawn which we’ll get into next.

Factor #2: A Shady or Sunny Location Will Affect Germination Rates

When I grow grass from seed at home in controlled environments I can usually get the vast majority of my seed to germinate within a 5 day window. If my first seeds sprout on day five then usually the last seeds are sprouting on day 10 or so.

When you are trying to get those seeds to germinate however you have to keep the soil surface and the seeds themselves moist all day every day. This usually means that you will be lightly watering them many times a day.

Once the first seeds germinate you still have to water frequently though because you have to wait for a critical mass of grass blades to appear before you dial back the watering frequency.

In a lawn setting it can be harder to keep seeds moist in a sunny or hot location. If you expect your seed to germinate in 7 days then that means you need to be prepared for 14 days of a frequent light watering schedule. For a sunny location some of your seeds are more likely to dry out causing patchy germination rates.

You could plan on watering your baby grass multiple times a day for a full month waiting for full germination or you could sow a heavier amount of seed and then switch to a more normal watering pattern after a shorter amount of time.

Unless cost is a significant barrier to your seeding project I would always apply more seed to ground surfaces in full-sun location with the understanding that not all of the seed will germinate in a reasonable amount of time due to the weather or other external factors.

Shady areas are typically easier to keep seed moist and get grass to start growing. Not only are they protected from harsh hot sunlight but shady areas are frequently protected from wind and rain a bit too.

Not all blends or breeds of grass seed are equally good at growing in the same places either. Some blends of grass are strictly designed for shady areas, while others will prosper only when sown in sunny, consistently well-lit areas of your lawn. Keep this in mind while selecting application rates for your project… and also keep in mind the next factor that can alter the amount of seed you use in your lawn.

Factor #3: Each Over-Seeding Project is Unique

You know this already – seeding a new lawn is a totally different beast than reseeding an existing lawn. When you’re working with an existing lawn you’ll likely require roughly half as much seed as you would otherwise but even then there are reasons to round up or down.

When the lawn you are overseeding is relatively thick and healthy and you only want to introduce a new cultivar into it then you may need less seed. There just won’t be a lot of space to fill between what grass is already in place.

On the other end of the spectrum really thin turf grass will have lots of gaps which means overseeding rates should be on the heavier side.

If you have a bad thatch problem in your lawn then seed to soil contact will be hard to come by so a heavier application may be warranted.

Does The Season Or Climate Affect How Much Seed You Need To Apply?

Here’s the good news: generally speaking, you don’t need to worry about seasonal or climate effects on the amount of grass seed you sow per square foot so long as you take the above factors into consideration. In general, as long as you’re paying attention to the directions listed on your given package of grass seed and you’re sowing it at the correct time and temperature, you won’t necessarily need to worry about what climate you’re growing it in.

With that said, it is important to take a close look at the label on your bag of grass seed. If you try to sow cool-season grass at the beginning of summer, for example, it probably won’t go too well for you, no matter how many pounds of grass seed you put down per square foot, or how much fertilizer and hay you lay on top of it to promote growth.

If you decide to seed in the early fall then you are far more likely to have positive results because the soil temperatures are high but the air temps are slowly cooling off. This helps with germination and root growth without the problems of heat stress and drought on your new grass.

In general, the given measurements for grass seed per square foot on any breed of grass seed only apply if you sow it during its intended season and with the correct conditions moisture, soil, light and temperature for the seed to properly germinate.

In that sense, sowing your seed during the correct season and when temperatures prove favorable is indeed important. It’s the only way you’ll know that your measurements are accurate and likely to produce the kind of yield you want for your next season’s grass.

Here Are Some More Ballpark Measurements To Get You Going In The Right Direction

In general, as long as you go for a couple of pounds of grass seed per 1,000 square feet of soil, you should be in the clear. Remember, though, that reseeding only requires about half as much seed as laying down a new lawn and there’s a coupld grass varieties that really do require less seed than that, so don’t go too overboard if you already have some grass to work with.

In general, most grass seeds won’t advertise more than five pounds for 1,000 square feet. 3-4 pounds is often a good range for seeding a new lawn, and 1-2 pounds/1,000 square feet is often around the recommended amount for reseeding.

In any case, remember to check the label of your grass seed before you go out and start the process; there’s no need to guesstimate how much you need if the answer happens to be right in front of you the whole time.

Can You Put Down Too Much Grass Seed? What Happens?

Yes, it is very possible to put down too much grass seed. In fact, putting down an excess of grass seed might mean that you end up with a less desirable outcome than you wanted for your lawn.

It’s kind of counter-intuitive. You’d think that the more grass seed you put down, the likelier the chance of having a lush, full-bodied lawn as the seeds sprout and grow. But that isn’t always the case. Simply put, there’s no extra benefit to putting more seeds into your soil than you need unless you plan on a large portion of them going to waste.

No matter how many individual seeds you spread each blade of grass ends up competing for a finite amount of ground surface and nutrients from the soil: water, minerals, nitrogen, sunlight, etc.

When you lay down an excess of grass seed, those resources get spread thin among all the competing seeds and new plants. Many will fail to take off and rather than having a nice, evenly spread lawn, you may get uneven growth as some areas get choked by the simple surplus of seeds.

If anything, you should seed at the rate listed on your bag of grass seed, or maybe even slightly lower. Even though it’s counter-intuitive, doing so will allow for the individual seeds to spread out and get an adequate supply of nutrients. That ensures that even if there are less seeds total, the ones you do have will grow tall and strong enough that your lawn will still look the way you want it to.

Plus, even if you underseed by a slight bit, it shouldn’t be a big deal. You can always come back next season and fill in the gaps with a little extra seed once you have at least a sparse, steady growth going. Overseeding, however, may ruin your hard work in the first place.

Of course seeding thicker will be more successful if you fertilize properly. Starter fertilizer will help establish strong root growth. See this post for more on the differences between liquid lawn fertilizers and granular lawn fertilizers.

Conclusion

Using the correct amount of grass seed per square foot will vary depending on the variety of grass, the season you’re sowing it in, as well as whether or not you’re seeding for a totally fresh lawn. Generally speaking, however, the number will be around a few pounds for every 1,000 square feet.

If you’re confused, or if that’s too vague a guideline for you, then don’t worry, scroll back up and consult the chart in the beginning of this page.

Finding the amount of grass seed you need by area isn’t actually too difficult. Just take a quick look at the label on your bag of grass seed. Or, if you don’t still have the original bag with you, look up the manufacturer online and find the specific variant that you have. You should be able to find a concrete number in pounds/1,000 square foot that will let you know exactly how much to use.

Also, don’t forget to seed in moderation. If you overseed, it’ll just have the opposite effect and make your lawn thin and scraggly. Either way, don’t sweat the small stuff; just find that number (or go with a ballpark measurement of a couple pounds per 1,000 square feet), get out there, and start contributing to your new lawn’s progress. It’s easier than it sounds, we promise!

Last parting thought – If you plan on installing a trampoline in your newly seeded lawn make sure to read our article on maintaining a lawn with sprinklers and a trampoline here.