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So you've got those old seed packets from last year (partially used or maybe even unopened)... but you're a little nervous about planting them. The package does say it was for the last growing year, and you're a rule follower.

How can you test your old seeds to see if they will still be viable in this year's garden? Testing older seeds is easy, and a bit fun, and I'll show you the best way to do it!

Why Test Old Garden Seeds

If stored properly, many seeds can last for years. Proper storing means they've been in a cool and dry environment. If stored properly, many seeds can last for years. Proper storing means they've been in a cool and dry environment.

I know many people who store their extra seeds in the freezer, and it works quite well. But if you're not sure about how well you kept your seeds stored, you may be hesitant to use them. See seed storage tips at the bottom of this post. 

Well, before you toss out that "old" package of seeds, here's a simple way to test them to see if they're still good! Even very old seeds can be tested for viability and if they were stored properly, they may still grow!

When performing a seed test, you're looking for the seed coat to break open and germination to take place. By mimicking a growing environment, you will be able to tell if most of your seeds will go through the germination process when you plant them. 

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Testing Expired Garden Seeds

This quick garden seed test takes just a few minutes to set up and then a few days of wait time. It's definitely worth the wait if you can use what you have instead of going out to the store to buy another package of seeds that you may not really need. 

If you have kids, they'll love checking on the seeds each day to see if they've sprouted! Here's what you'll need to test your seeds:

• Paper towels
• Sharpie
• Seeds
• Water

Chances are, you have all of this stuff laying around your house, so let's get started!

Steps for Seed Testing

Here are the step-by-step instructions for my at home germination test:

1. Take one sheet of paper towel and dampen with water. Lay damp paper towel on table or counter and place 2 or 3 seeds on the towel. I would use one type of seed per paper towel, so you can remember what seed type you're testing. Here are some of last year's beet seeds:

2. Roll seeds up in the damp paper towel. It will look like a paper towel cigar, but just don't go lighting it up. Use your sharpie to write on the outside of the towel what type of seeds are in there. The writing will get a little "loose" as you keep the towel wet over the next few days, but you should still be able to tell what you've written.

3. Place the rolled paper towels on a plate or low-sided dish and let marinate for a few days, keeping the towel damp. I do this by putting a little water in the bottom of the plate and letting the towel soak it up; you could also spray it with a water bottle.
4. Open up the paper towels and see if the seeds have sprouted! If your seeds are still good, you will see shoots popping out of the seeds. If you're not seeing sprouts, you could wait another day or so (this may be necessary for seeds with a longer germination period, and you can find this info on the seed pack itself).

You can see most of our beet seeds sprouted, as well as the garden peas I tested. And that poor pack of garden peas was in rough shape from being left out in the rain (oops!), so if they sprouted, you can feel good about testing whatever old seeds you have laying around.

And that's all there is to it! Simply taking a few seeds and testing them for seed germination can save you having to buy all new seeds this year, especially if you square-foot garden. Since you only use a certain number of seeds with the Square Foot Gardening method, I find that I'm able to use one package of seeds for two years or longer.

Seed Storage Tips

To have a better chance at your seeds being viable longer, your best option is to store them properly. Here are some tips for the best storage conditions for your fresh seeds:

Proper seed storage helps maintain viability for future planting. Here are three key tips:

1. Keep Seeds Cool and Dry – Store seeds in a cool, dry place, ideally between 32–50°F. A sealed container in the refrigerator or a dry basement works well. Avoid humidity, which can cause mold or premature germination.
2. Use Airtight Containers – Store seeds in airtight glass jars, plastic containers, or resealable bags with silica gel packets to reduce moisture. Label each container with the seed type and collection date. I love these photo storage bins for all of my seed storage needs. 
3. Avoid Light and Temperature Fluctuations – Keep seeds in a dark place, away from direct sunlight or heat sources. Sudden temperature changes can reduce viability, so maintain a consistent storage environment.

Now, let's move onto tips for starting your garden seeds. 

Seed Starting tips

Starting garden seeds at home can be a rewarding and cost-effective way to grow plants, and you can choose from a much larger variety. Here are four tips to help you succeed:

1. Use Quality Seeds and Proper Containers – Choose high-quality seeds suited to your climate and season. Use seed trays, small pots, or any clean containers with drainage holes to prevent water logging.
2. Provide the Right Soil and Moisture – Use a light, well-draining seed-starting mix rather than regular garden soil. Keep the soil consistently moist but not soggy to prevent mold and root rot.
3. Ensure Proper Light and Temperature – Most seeds need warmth (65–75°F) to germinate. Place trays in a warm spot or use a seedling heat mat if needed. Once sprouted, provide ample light using a sunny windowsill or grow lights for 12–16 hours a day.
4. Harden Off Before Transplanting – About a week before moving seedlings outdoors, gradually expose them to outdoor conditions. Start with a few hours of indirect sunlight and increase exposure daily to strengthen them.

More Seed Starting Helps

Whether you're just starting gardening or have been growing for years, these articles may help you in you gardening journey:

• The Best Seed Companies with Free Catalogs: Order any of these free catalogs that have helpful articles and fun seeds varieties, and best of all, they're free! It's always a good idea to have helpful gardening resources on hand. 
• Seed Storage Ideas: Not sure how to keep your seeds organized for next year? Check out this full post with ideas on how to store garden seeds. 
• How to Start Tomato Seeds: Tomatoes can be a pretty finicky garden plant, so start out strong with healthy seedlings. Check out this full article on planting tomatoes!
• How to Harvest and Store Tomato Seeds: Did you know tomato seeds can easily be saved at the end of each season? This can give you an almost endless supply of tomato plants. Find out how easy it is!