Does Grass Seed Go Bad A Top Guide For Beginners

If some seeds are only viable for 3 to 4 years,does grass seed go bad as well? Gardeners look forward to restoring their yards’ lush green lawns each spring. Some of us even purchase large quantities of lawn seeds, with the extra typically being kept in the garage until spring.

For a gardener, nothing could be more depressing than expired seeds and supplies. We’ll discuss the durability of grass seeds in this post, along with the methods of preservation that farmers employ.

In order to prevent you from lamenting the loss of your expired and rotten seeds, we will also share the factors that affect the viability of the seed.

Keep reading.

How Long Does Grass Seed Last?

Yes, grass seeds go bad or expire, but there’s more to them than that. That grass seed is still viable or alive can be determined by two different factors. These factors include the moisture content and germination rate of the grass seed.

The label of the grass seed you purchased typically states the germination rate. The likelihood that grass seeds will sprout into seedlings is determined.

For the first year, germination rates typically range from 80% to 90%. However, the germination rate of grass seeds usually declines by 20% to 10% annually.

If you’ve been gardening for some time, you probably already know that you must plant more seeds to make up for their poor germination rate. You’ll need to plant more seeds if you use a 3-year-old grass seed from your garage to get the desired amount of grass to grow.

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Grass Seed Shelf Life

Grass seed has a best-before date just like the majority of other naturally occurring goods that have a shelf life. Try to use your grass seed within two to three years of purchase as a general rule. After the first two years of storage, keep in mind that the likelihood of seed germination will decline by about 10–20% per year.

Let me give you a quick example:

Only 1 in 5 seeds may germinate if the bag of seeds is older than ten years. Not good right?

Try to use those seeds as soon as possible, or at the very least, within the first two years of purchase. After all of that, it all depends on how you store your seeds; we’ll talk more about that later.

What Is The Shelf Life Of Grass Seed?

There is more to determining how long grass seed lasts than simply stamping an expiration date on the bag. Although an unopened bag of seeds may last longer than an opened one, how you store it does have a significant impact on how long it will stay viable.

While an unopened bag of grass seed will last for at least five years, an opened bag can last up to 18 months when properly stored. How do I know this?

Well, those who are knowledgeable than I am, i.e. the experts at the According to the Oregon State University Seed Lab, grass seeds that grow in hardiness zones 3 to 9 (like ryegrass) can last up to 5 years if stored properly.

The typical storage life of other popular grass seed varieties like Bermuda or Fescue is three years. You will need to use more grass seed to cover an area because some of it won’t sprout because the chances of germination are still reduced while in storage.

When It Expires, Does Grass Seed Go Bad?

It can be challenging to determine if grass seed is past its expiration date if there are no outward indications that it has begun to degrade, as the date printed on the bag is only a rough estimate. Your method for storing grass seed will determine everything.

If you’re on the fence about sowing the expired seeds, carefully examine the seeds for evidence of fungi. Throw them away if they are clumpy or damp. This indicates improper storage of them.

Do Expiring Seeds Still Grow?

I can assure you from my own experience that using expired grass seeds won’t affect the outcome. Why?

According to the manufacturer’s expiration date printed on the packet, grass seed does, in fact, expire. But does this impact seed germination?

The majority of people rely far too heavily on the products’ expiration dates. A packet of grass seeds may have a “sell-by” or “best-before” date if you check the date on it. Additionally, some seed packets include a “sow-by” date that doesn’t even reflect the freshness of the seeds.

Consequently, the query “do expired seeds still grow?” has an answer.’ is a big YES, just as you would with their fresh counterparts, you will still receive fruitful harvests from expired grass seeds. However, you should perform a quick test to see if your expired seed successfully germinated just to be safe. A little later, I’ll share my seed testing hack.

See more about How Long Does New Grass Take To Grow?

How Should Grass Seed Be Storied?

You probably couldn’t wait for this section! Right, here it goes…

The grass seeds’ longevity is significantly impacted by the storage conditions. Even though the majority of people might suggest an outdoor shed or garage for storing your seed, those spaces aren’t ideal because of the exposure to humidity and heat.

You might scowl if I suggested keeping your sealed bag of grass seed in the refrigerator next to your carton of milk because you don’t have enough room.

Okay, so this might not work for everyone, so try to find a cool place, like a cellar or basement, as long as they are completely dry and the temperature is kept between 40 and 55 degrees Fahrenheit.

Nevertheless, think twice before you exclaim, “Whew, that was simple.” we’re not done yet with the seed storage advice! For a few more hints, keep reading.

Useful Grass Seed Storage Tips

  • The storage area must be cool, dark, out of direct sunlight, and dry; ideally, it should be in an air-conditioned room.
  • Make sure there is enough airflow throughout the bag of seeds, even if it is still sealed.


The seeds should be kept in a mesh air vent-equipped bag with good ventilation. The mesh allows for the best airflow while keeping insects from getting to the seeds. Since the goal is to prevent mold growth and maximize airflow, burlaps will also work.

To reduce moisture buildup, keep seed bags apart from one another.


To lessen the possibility of moisture or fungi, put a container of baking soda inside the grass seed bag.

If you’re not going to use the entire bag of seeds to cover your patchy lawn, make sure to properly store the extra seeds in the mesh bag or burlap I mentioned earlier.

  • Keep in mind that if you want to get the best results from using old grass seeds that have been stored for more than three years, you must sow the ground more heavily.

Is Grass Seed Freezable?

As long as you only freeze your grass seed briefly, it won’t lose viability.

There is no reason why you cannot temporarily freeze your grass seed since sown seeds frequently do not germinate during freezing temperatures. In total, one or two brief freezes shouldn’t have an adverse effect on the quality of your grass seeds.

Does Grass Seed Go Bad A Top Guide For Beginners
Does Grass Seed Go Bad? A Top Guide For Beginners

How Can You Tell If Grass Seeds Are Expired?

These days, everything has a date of expiration, even grass seed. Buying seed from your neighborhood home and garden store will have a sell-by date on it. Your seeds are not actually “expired” in the sense that we think of milk that has gone bad if they are past their sell-by date; rather, germination will be less effective. Even so, make sure to conduct a visual inspection because the development of mold or fungus may be a sign that moisture has harmed the grass seed.

The viability of the seeds can also be determined by conducting a DIY germination test. Simply place 10 seeds in a sealed plastic bag on a wet paper towel. Check for germination after 10 days by keeping the bag in a warm location. Less than 50% of the seeds will sprout if you find that fewer than five of them did. You should plant twice as much as is advised at a 50% viability.

Which Seed Should I Purchase?

The best grass seed selection involves a number of considerations.

You must first think about the local conditions.

That’s a fancy way of saying: what is your lawn like?

Do you, for example, reside on a lot that is shaded? Is your lawn primarily made of sand or do you have a lot of heavy clay soil?

What kind of seed will flourish and perform best in your lawn will depend on the conditions there. It might be a different variety of grass than what your neighbor across the street has.

However, a good general rule of thumb is to purchase an all-purpose grass seed that is suitable for your area (warm season grasses in the southern half of the US, cool season grasses in the northern half).

Blends of seed offer a variety of grass types, some of which will typically perform better in shaded areas than others, and you’ll have good coverage throughout your entire lawn.

You can address problem areas later after seeding your entire area with the all-purpose seed.

How Do I Choose A Brand?

When buying grass seed, it is also wise to go with a reputable brand.

Seeds with cracks and breaks gather moisture and eventually don’t sprout. A lush, green lawn can be achieved faster and with less reseeding if the grass seed is of high quality and contains fewer damaged seeds.

Scotts, Jonathan Green, and Pennington are three quality brands consumers have grown to trust over the years, and you can buy seed from these brands online on Amazon (Amazon links: Scotts, Jonathan Green, Pennington), or locally at your hardware store or local big box retailer.

I use Jonathan Green seed which I purchase straight from the producer. I discover that doing this gives me the freshest, highest-quality seed. This one is my go-to and I fervently advise it.

Grass seed is expensive, but the cost of high-quality seed is justified by the fact that it requires less seed to get a good start.

Having said that, many branded grass seeds primarily contain fillers and mulch that aid in germination. I advise getting grass seed that is 100% seed unless you are only doing a small area of lawn.

There are other reliable brands, but if you’re shopping for grass seed for the first time, you will probably have good results with Scotts and Pennington, or fantastic results with Jonathan Green.

These three are consistently praised for producing quality turf, and Black Beauty Ultra from Jonathan Green is what I use in my lawn.

What Else Should I Take Into Account Before I Buy Grass Seed?

Make sure the bag you select at the store has not been opened because moisture is detrimental to your seed’s productivity.

Before taking the bag home, make sure there are no tears.

A grass seed bag can become contaminated with pathogens that rot and degrade the seed with even the smallest amount of moisture. No matter how much you water it, this will cause it to spoil and prevent it from germinating.

Take note of how the bags are arranged on the shelf as well.

To allow air to flow around them, arrange them upright with some space between each stack.

The amount of airflow is restricted by seed packages stacked on top of one another. They may begin to collect moisture if they are kept in this manner for an extended period of time, which will lower the rate of germination.

Oh, and you can look in the bag’s back. There is usually a date printed somewhere on grass seed bags, so if you have a shelf full of seed, you might find some bags that have been there for years and some that were only bagged last month.

Always choose the freshest.

Frequently Asked Questions 

Is It Acceptable To Use Stale Grass Seed?

Utilizing stale grass seed is acceptable. Expect a low germination rate and poor seedling quality, though.

The odds of the grass seeds germinating decrease by 10% if they are from your stock from the previous spring. You might therefore need to apply more grass seeds than what is advised.

Can Grass Seed Spoil In A Bag?

In contrast to an opened bag of grass seed, it will take 3 to 5 years before it can expire. You can delay the decline in their viability as long as you store them in a cool, dry, and dark location.

When Frozen, Does Grass Seed Lose Its Freshness?

In fact, grass seeds are baked at very high temperatures. Only temperatures above freezing, in the 40F to 50F range, should be used to store them.

Old Grass Seed: What Should I Do With It?

Sprouting ten seeds in a zip-lock bag will allow you to gauge the germination rate. Even if the seeds took root, you can still plant them in spring to cover the bare spots in your lawn. Alternatively, if the grass seeds are no longer viable, you can add them to your compost pile.

What Is The Time Required For Grass Seed To Sprout?

Grass seeds usually take about 5 to 10 days to germinate. On the other hand, the length of time depends on the type of grass and the germination environment.

You can anticipate them to sprout in five days if the grass variety’s germination requirements are met. In order to guarantee that you will achieve your desired coverage if you are using an old seed with a low germination rate, you must also add more seeds.

Can I Keep Grass Seed In The Garage?

No, the viability of your grass seed can be impacted by the freezing temperatures in the garage during the winter. Additionally, it might encourage the accumulation of moisture, which would hasten the loss of viability of the grass seeds.

You can keep it there, though, if your garage is connected to your HVAC. To make sure there is no moisture present, you can put a desiccant in the container.

Final Words

We sincerely hope that this post has given you a better understanding of how to properly store and care for your seeds. As long as the recommended seed processing and storage practices are followed, seeds can last for a very long time.

As soon as they are separated from the mother plant, the seed variability’s timer begins. Some seeds stand out from the rest when they are properly processed and stored, and they are typically priced higher on the market. In order to minimize waste, it’s still best to only purchase seeds as needed, regardless of quality.

We strongly urge you to share any tips you may have with our community if you have a special method for storing grass seeds. To encourage more farmers to preserve and take advantage of lush green lawns, share your technique in the comments section below.

I appreciate your reading.