If you happen to have leftover grass seed from previous years or you have bought more than you need for this season, you may be wondering does grass seed go bad?
The good news is that, unlike many other seeds, grass seed is more resilient and can last for 2-5 years if stored properly.
The grass seed should be stored in a dark, dry, and cool place to prevent it from germinating or going bad.
Read more about preserving it properly, how long it can last, the factors that affect their longevity, and everything else you need to know about grass seed going bad.
The quality of the grass seed is essential
The quality of the grass seed is a major factor for its germination rate and for its longer shelf life.
The germination rate refers to the rate of seeds that will actually sprout and is impacted by the way in which the seeds have been harvested, the location of their production, the storage, and other factors. So, they are out of your control.
In order to ensure that the grass seeds are viable and are of good quality, check the labels before buying them.
You should pick seeds that guarantee a germination rate of 80% or higher. Also, check the tested date of the seeds, and keep in mind that the germination rate will decrease with every next year, so it is best to use the seeds in the first year after their packaging.
Plus, it would help if you tried to buy your seeds from reputable stores and distributors which grow, package, and store the grass seeds in accordance with the industry standards.
Still, if you have an old bag of grass seeds, you can still use it for projects such as overseeding and other non-essential projects.
The proper storage conditions
Storing the grass seed in ideal conditions can help promote longer shelf life and maintain a high germination rate even after the first year of packaging. According to some lawn experts, the grass seed can remain viable for 2 and even up to 5 years when stored properly.
Keep in mind that the germination rate of grass seed will decrease by 10-20% every year after the purchase. This means that you will need more seeds for reseeding your lawn or other planting areas.
The grass seed needs to be placed in airtight sealed containers right after being harvested. Bagged grass seeds are more prone to being affected negatively by humidity.
While the grass seed stored in bags for over a year may still be viable and used, chances are that you will need more seed to achieve the effect you want.
Keep the grass seed away from moisture, direct sunlight, and pests
When storing the leftover grass seeds, make sure that the bag or container is out of the direct sunlight and rain and is placed in a cool and dry place.
Too much humidity can cause the premature sprouting of the seeds or can lead to fungal infections and the growth of mold.
Pests such as rodents can be a problem too, as they will eat the seeds but leave the husk behind, leaving you to believe that the bag is full and can be used.
When storing the grass seed, make sure that you protect it from extremely hot or extremely cold temperatures, which means that it is not advisable to store the seed outdoors.
Does grass seed go bad – how to store the seeds?
To increase the viability of the seeds, make sure that you store them in suitable containers which are properly sealed. Seeds in bags or left in the open will attract and absorb moisture which can cause sprouting, mold, fungus, and other problems.
If your seeds are in bulk storage bags, you can keep them there if you are planning to use the seed within a year.
If you are storing the grass seed in bags that have perforations, make sure that you keep them away from rain and moisture and somewhere where there is sufficient airflow.
If your seeds are in burlap or other breathable bags, then you can place a container full of baking soda next to them, which will help absorb excess moisture from the air.
If you have leftover seeds, place them in a suitable sealed container or bag, and add the date of their germination testing, purchase, and opening.
Before planting the seeds, check them for any moisture, mold, and mildew.
How do you tell that grass seeds have gone bad?
While you can store grass seeds for a few years safely, just like with all other types of seeds and products, they have an expiration date.
Check the sell-by date of the seeds. This is the date when the germination rate will begin to decrease, so you can still use the seeds, but you may not be able to achieve the best results when planting them.
Before using the seeds, check them for moisture damage, fungus, and mold or pest invasions.
You can also perform your own germination test by placing a few of the seeds on a piece of wet paper towel and inside a sealed clear plastic bag in a warm area. Keep an eye on the seeds for the next 10 days, and count how many of the seeds have sprouted. This should give you an idea of what germination rate to expect when you plant them.
If the germination rate is about 50% (only 5 out of 10 seeds have sprouted), then you may want to use twice the amount of grass seeds you would normally use for your lawn or other outdoor space.