Alfalfa (Medicago sativa L.) is a crop characterised by presence of hard (dormant) seed that are viable but do not germinate in seed quality testing. In Republic of Croatia seed are frequently stored for three to four years due to low needs for seed of alfalfa and considerable import. The share of hard seed is decreased by storage time, temperature and air moisture changes and therefore directly keeps the level of seed germination in a longer period of storage.