Volunteer Eve Dixon places cleaned and counted
Sericocarpus rigidus (Aster curtus) seeds
in envelopes for storage.

The Miller Seed Vault is the largest vault of its kind in the Pacific Northwest. Reinforced for earthquake protection, the 150-square-foot vault has a work room, a short-term storage room, and a long-term storage freezer. The environment in both the work room and short-term storage room are maintained at 15 degrees C (57 degrees F) and 22% relative humidity to quickly dry the seeds and keep them dry as seeds are cleaned, counted, and processed for long-term storage. 

Seeds being held for ex situ conservation are ultimately placed in the long-term storage freezer. These seeds are placed in foil laminate bags and heat sealed to moisture-proof the contents. The temperature of the freezer is –18 degrees C. At this temperature, we expect many of these seeds to survive for decades before they lose viability.

The storage room provides space to hold larger quantities of seeds intended for use for restoration and research and is intended for holding seeds for shorter time periods (typically up to five years). Rare Care provides this service for free. Contact Rare Care if you are interested in storing your seeds in the Miller Seed Vault.