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I Didn’t Know That!

By Judy Kunz, Colorado Master Gardener

Seed Inventory Time

It can be discouraging to sow seeds in the spring with the hope of seeing the first leaves peek out of the soil, only to have nothing happen. Outdated seeds are frequently the culprits in this disappointing scenario. Taking the time to check seeds now and discarding those that are old or non-viable can save frustration and lost growing time in the garden later.

It’s no secret that the price of garden seeds has risen like everything else in the last few years, so saving them makes sense. However, seed viability declines over time and, depending on the seed type, some may last only a few years, even under favorable storage conditions.

Seed packets and testing, Photos:

To verify seed viability, try this easy method. Count out 10 seeds and roll them loosely in a damp (not wet) paper towel. Secure them in a zipper-type plastic bag and set them in a warm place. The top of a refrigerator is an ideal spot to encourage germination. Check them in a few days but allow the maximum germination period stated on the seed packet. The number of sprouted seeds indicates the percentage of viability, i.e., seven out of ten seeds successfully germinating = 70% germination rate. Discard any seeds that have a poor germination rate of less than 50%.

To maximize seed viability, always store them in a cool, dark place in an air-tight container. The recommended method is to store packets in a sealed jar in the freezer. But if freezer space is limited, a basement can work because of its cool environment.

For further information on storing seeds and a longevity chart, see this fact sheet:

Storing Vegetable and Flower Seeds – 7.221 – Extension (

Flower seed viability chart:

Seed Storage & Seed Viability Guide | Johnny’s Selected Seeds (

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