Tips, Tricks and Hacks

Learn how to check if seeds are still good to use and how to store them for future growing seasons.

If you’re like most gardeners, you probably have half-opened or extra packets of seeds left over from past growing seasons. But how do you know if seeds are still good? After all, most climates have a relatively short growing season, and we don’t want to waste time on seeds that will never sprout.
“Seeds are living things that contain moisture, and if they dry out, the seed dies,” says Gary Pilarchik of The Rusted Garden and author of The Modern Homestead Garden. “If you’re storing them correctly, they’ll last longer than you think.”
Although it’s fun to buy new options every growing season, you can save money if you hang on to your extra seeds properly. “Most of the time, these seed packages have hundreds or even thousands of seeds in them,” says Pilarchik. “You’re not going to plant all of them, so if you save the seeds correctly, you can get another planting season or two out of the same package.”
Learn how to check if seeds are still good to use and how to store them for future growing seasons.
How long do seeds last?
Whether you’ve saved seeds from your own crops or purchased them, storage conditions can impact how long your seeds will last. Most seeds remain viable from two to five years. If you keep them cool, you may get five years or longer, says Pilarchik.
He suggests keeping them in their original paper seed packs, then storing those inside a zipper-top plastic bag to help them retain moisture. If possible, placing the plastic bag in the fridge helps even more, as the cold can prolong its lifespan.
A quick exception: There are a few types of seeds that only last 2 to 3 years, says Pilarchik. That includes corn, onion, leek, carrot, spinach and lettuce. Many herb seeds also don’t germinate well after a season or two, even if stored properly.

How to check the quality of extra seeds Seed packets are stamped for the year in which they’re packed, but this doesn’t indicate an expiration date, says Pilarchik. Instead, perform a few basic tests to see if the seeds are still good before planting:

Inspect larger seeds. These include pumpkins, zucchini or squashes. If they’re dried out and wrinkled up or soft, mushy or smelly, they’re no good.

Place seeds in a cup of water. Wait for 15 minutes. Any seeds that float are dried up and not viable.

Do Germination Test

This is the most effective test for all types of seeds. Place 10 seeds in a damp paper towel; the towel should be wrung out, not sopping wet. Fold it over a few times, then place in plastic bag in a warm area, such as on top of your fridge. Make sure the towel doesn’t dry out. Read your seed packet for germination times for a specific seed, but most seeds should germinate in about 5 to 10 days. Check seeds starting from day 5. If only some of the seeds germinated (say, 4 out of 10), that’s a 40 percent germination rate. That’s not great—but you still can plant the seeds; just plan to put more in each hole to ensure you get good germination, says Pilarchik. For lower germination rates, it’s worth buying new seeds. Taking the time to do a germination test also saves you money because now you can buy only the seeds you really need and focus the rest of the budget on any fun, new seeds you see when shopping.