Answer: If seeds are properly stored you can expect the germination rate to remain high for 2-3 years. After that the rate declines, and very old seed may not germinate at all. The secret is in handling and storage, and it doesn't usually matter whether or not the seed packet has been opened. If you can't plant your seeds right away, store them in an airtight container, in a cool, dark location, such as the bottom of a closet or back of a seldom used cupboard. Heat, light and moisture are the real enemies of stored seed. If you keep yours properly stored, they can remain viable for a number of years. To test the germination rate of seeds, place 10 between the folds of a damp papertowel and seal in a plastic bag. In 7-10 days check to see how many have sprouted. The number of sprouting seeds will give you a rough estimate of the percentage of germination for that batch of seeds.
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