Martha Stewart: Seeds should always be stored in a cool, dry place, says Linda Langelo, horticulture specialist at Colorado State University, adding that the area should ideally be around 45 degrees Fahrenheit and have less than 8 percent humidity. The basement, a dark closet, or the refrigerator are all good options. Avoid storing seeds in sunlight or an area with high temperatures and humidity, which will speed up degradation.

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