You may have a leftover bag of old grass seed from the previous year or the year before on hand, and it is time to patch up some bare lawn area that could use some reseeding. You may find yourself asking does grass seed go bad? Is it still viable to use? In this article, we will help you determine if your leftover seed is still good enough to use.
Does Grass Seed Go Bad Or Expire
The short answer is grass seeds may go bad as they are living organisms after all. But before you throw away your old grass seed, there are a number of ways to determine if your grass seed shelf life is still good enough to use for your lawn.
Storage Conditions
The ideal prime period to use your grass seeds is when they are less than one year old. If your bag of grass seed has been stored in a cool and dry place, the seeds may still be good enough to use in your lawn.
Grass seed may last up to two to three years on average. Some can last up to 5 years or more if proper storage is provided. Different seed types have different storage requirements and have different needs for staying viable.
With older seeds, you may not get the same result as fresh seeds, but you may still be able to germinate and plant the seed. In other words, if your fresh seed promises a 90 percent germination rate, that will probably drop to about 80 percent in year two, and the grass seed decreases another 10 percent the year thereafter. This will just mean you will need to use more seed.
When purchasing grass seed, purchase high-quality grass seeds from a reputable brand. Usually, they have a higher germination result.
How To Germinate Grass Seeds
To determine if your grass seed is still good or not, simply test it through germination. Grass seeds should germinate between 10-14 days. To germinate, you will need a cup or a shallow dish and a paper towel. Sprinkle your grass seeds (at least ten seeds) on top of the paper towel and water until your paper towel is fully wet. You may put a plastic bag on top with a hole to create a mini-greenhouse effect. Then place it in a warm and sunny window. Be sure to check it daily to make sure the paper towel isn't dried out and add water when needed. Once germination happens, you can determine the grass seed's viability rate. And when the grass is fully grown, it can be on the same watering schedule as the rest of your lawn.
Why Grass Seed Didn't Grow
If you throw the grass seed in the bare spots in the yard and nothing happens, a few conditions can affect the seed viability.
- Germinating conditions. If you apply the grass seeds during the spring season, the cold and wet weather can hinder the germination process. The soil temperature needs to be consistent at 55 degrees, and the air temperature needs to reach at least 60 degrees Fahrenheit for grass seed to germinate.
- Moisture levels. Excess spring rain or too much water can hinder germination. While grass seed does need watering, overwatering will not help for growth. If you are growing it in your lawn, you only need the top inch of soil moist until germination occurs.
- Lack of sunlight. Germination happens in sunny and warm weather. An area that only receives 1-2 hours of direct sunlight can be a challenge to grow grass seeds.
Check Germination Rate And Expiration Date
Everything comes with an expiration date these days, and that includes grass seed. Store bought packaged grass seeds to come with a tested date and a germination rate. The germination rate is the rate you can expect your seed to germinate within the first year post packaging. Usually, stores bought grass seeds to have an 80-90% germination rate. And then, the germinate rate will decrease 10-20% each subsequent year of storage.
Appearance
When opening your store grass seed, make sure the texture isn't clumpy and does not have any foul smell or moldy.
How to Store Grass seed properly
Proper storage of grass seeds can expand their shelf life and maintain viability, as it keeps them fresher and lasts longer. The ideal conditions for grass seed storage are in cool, dry, and dark space like a basement, garage, or a cellar rather than a place garden shed.
Container
A container is usually recommended for long term storage as it will help keep your leftover grass seed last longer by keeping moisture and humidity out. But the content should not be enclosed or damp. It should be able to keep insects and rodents away.
Storing grass seed in a breathable material like a burlap bag or bag with mesh air vents will reduce molding risk and allow a good air flow. However, it will put your grass seed at risk of exposure to moisture. For best results, placing an open baking soda near it will help minimize moisture.
Moisture
Moisture seeds should be kept dry and prevented from absorbing moisture and humidity as they will reduce shelf life and even let the grass seeds go bad.
Ventilation
Your grass seed is a living organism, and it needs a well-ventilated area with constant air flow to maintain its viability. This will prevent mold from growing and keep your seeds fresh, or else the seeds can suffocate.
Temperature
The grass seeds should be kept dry and at a temperature that is not too cold to cause freezing, nor too much heat or relative humidity. The ideal storage temperature is below 60 degrees and less than 60% humidity.
How To Properly Store Leftover Seeds
If you can't finish an entire bag of your seeds in the same year, store them in a cloth sack or burlap bag for next season. This material will allow good airflow. Place an open consideration of baking soda next to it to eliminate any unwanted moisture. It keeps them fresher and lasts longer. The ideal conditions for grass seed storage are cool, dry, and dark space like a basement, garage, or a cellar rather than a place garden shed.
Container
A container is usually recommended for long term storage as it will help keep your leftover grass seed last longer by keeping moisture and humidity out. But the container should not be enclosed or damp. It should be able to keep insects and rodents away.
Storing grass seed in a breathable material like a burlap bag will reduce the molding risk and allow good airflow. However, it will put your grass seed at risk of exposure to moisture. For best results, placing an open baking soda near it will help minimize moisture.
Moisture
Moisture seeds should be kept dry and prevented from absorbing moisture and humidity as they will reduce shelf life and even let the grass seeds go bad.
Ventilation
Your grass seed is a living organism, and it needs a well-ventilated area with constant airflow to maintain its viability. This will prevent mold from growing and keep your seeds fresh, or else the seeds can suffocate.
Temperature
The grass seeds should be kept dry and at a temperature that is not too cold to cause freezing, nor too much heat or relative humidity. The ideal storage temperature is below 60 degrees and less than 60% humidity.
Leftover Seeds
If you can't finish an entire bag of your seeds in the same year, store them in a cloth sack or burlap bag for next season. This material will allow good airflow. Place an open consideration of baking soda next to it to eliminate any unwanted moisture.
