Arrhenatherion meadows are an endangered type of semi‐natural grassland in Europe, and their conservation and restoration is an important policy objective. Recent research has led to development of techniques for harvesting seed material from regional donor sites and strategies for re‐establishment of species‐rich grassland, but their practical application requires that consumers are guaranteed sufficient seed quality of directly harvested material. Methods for the evaluation of purity, thousand seed weight (TSW) and germination capacity were developed and tested, a pre‐condition to define the optimal seeding rate for this vegetation type (2000–3000 seeds m−2). The assessment was based on seed obtained by two harvesting techniques: on‐site threshing (OST) and seed stripping (SS). Materials from both methods obtained 63% pure seeds. The TSW differed significantly between harvesting methods: the OST provided greater seed weight (1·057 g) than the SS (0·84 g). Two trials were implemented to define criteria for the germination capacity test. Organic growing media obtained the best and most homogenous results in a first comparative germination test. In the second trial, different dormancy‐breaking treatments were compared, each with and without pre‐chilling, namely: addition of potassium nitrate (KNO3), addition of gibberellic acid (GA3) and without addition of chemicals (WA). The germination capacity of the treated variants KNO3, GA3 and pre‐chilling was lower than that for WA. The harvesting method significantly influenced quality and quantity of the seed material, whereas the substrate and dormancy‐breaking treatments had no effect.

Neither methodology nor guidelines are available for defining quality characteristics and storage conditions of seed material harvested from semi-natural grassland. Seeds from an Arrhenatherion meadow were harvested via on-site threshing and seed stripping. After determination of purity, thousand seed weight and pre-tests in a phytotron, germination-capacity trials were carried out in a greenhouse. The harvested seed material was stored for up to 3 years under different conditions: (i) room temperature 18-23°C, (ii) cooling chamber (2-5°C with 40-50% humidity) and (iii) freezer (À18°C). There was a significant impact of the tested harvesting methods on seed separation, thousand seed weight and purity, but not on the germination capacity. Different storage conditions and storage length significantly influenced the germination capacity. There were also generally higher germination values for the seed-stripping material than the on-site threshing material (ca. 70 and 60%, respectively, in the first year). Germination capacity decreased significantly with time and was <15% after 3 years. We conclude that harvested seed material from semi-natural grassland should preferably be stored under cool conditions and used within 2 years.