The step between seed harvesting/processing and sowing is a critical one. Inappropriate seed storage will result in deterioration of seed quality. As a general rule, if you can do nothing else, keep seed dry and avoid extreme temperatures. The moisture content of seed is more important than the ambient temperature in maintaining a viable seed lot. Seed storage life can be doubled for every 5°C decrease in seed temperature and by each 1% decrease in seed moisture content. Generally, if seed is properly dried, (6–10% moisture content) and stored at low temperatures (5–20°C) in sealed containers, it will remain viable for a long period of time.
The normal storage life of native grass seed depends upon the species and can vary greatly. Given conditions of very low humidity (
FloraBank (www.florabank.org.au) has a number of publications that describe in detail how to collect and store native seed. These guidelines, whilst primarily developed for tree species, are appropriate for storage of native grass seed. The guideline 'Native seed storage for revegetation' (www.florabank.org.au) details three relatively low cost procedures for short-term ('Guideline 3 - Improving on basic native seed storage' (www.florabank.org.au) is useful for those who have already commenced seed storage, providing a guide to improving storage practices to store seed for longer then 5 years. Both publications are pitched towards public revegetation groups and/or small-scale commercial collectors.