Too much moisture and seeds may get damping-off, a disease problem that causes the seeds to rot and die. Improper soil temperature. Some seeds germinate better when the soil temperature is cool, including spinach, lettuce, and radishes. Other seeds need to have a warm soil to prevent decay, including sweet corn, beans, squash and pumpkins. I didn't use all my seeds.
Extra seeds are great for sharing with neighbors and friends, school groups, and community gardens.
Most seeds will germinate for 2-3 years. However, the rate of germination will go down. Seeds need to be stored properly in an area where they will be kept cool and dry. The best way to keep seeds is to store them in your refrigerator in an airtight container such as a glass jar with a tight-fitting lid or Tupperware. By Federal law, any treatment is required to be printed on the label.