Center for Plant Conservation - Seed Banking

Key Messages about Conventional Seed Banking

• Seed banking rare plant species is an important way to safeguard genetic diversity long-term. The best conservation collections will capture diversity of 50 mother plants into separate packages such that as many as 3000 seeds from each of five populations across the range of the species are secured.
• Because not all seeds can be stored in a freezer, understanding the seed storage needs of the target species is critical prior to investing major time and effort in a large collection. Prepare for collecting by reviewing species’ details, obtaining permits, and determining how seeds will be able to be stored.
• Under most conditions, CPC advises collecting no more than 10% of a seed crop in any year and no more than 5 of 10 years. The exception is an extremely threatened population, which may require collecting from all individuals to ensure safe duplication.
• To ensure greatest longevity of orthodox seed, process seeds in cool, dry conditions, dry seeds to a moisture target that maintains < 25% RH > 10% at the intended storage temperature, and store seeds at -20°C or less.
• Extremely small accessions may require recollecting over multiple years or generation to collect next generation seeds for storage.