Seed quality of chamomile (Matricaria recutita L), lemon balm (Melissa officinalis L.) and valerian (Valeriana officinalis L.) on the German seed market in 2009 to 2011

In 2009 to 2011, the seed quality of chamomile (Matricaria recutita L.), lemon balm (Melissa officinalis L.) and valerian (Valeriana officinalis L.) on the German seed market was studied with respect to the quality parameters purity, germination capacity, content of foreign seeds and thousand-seed-weight. The results were compared to the newly published quality suggestions in the "Manual of Medicinal and Spice Plants Cultivation" (Hoppe 2009) as well as the standard of the former TGL14197 of the GDR. Only 42% of all chamomile seed charges met the suggestions according to Hoppe 2009 and 50% the quality criteria of the GDR-TGL 14197. In case of lemon balm and valerian, the respective values were 36% and 9% (Hoppe 2009) as well as 64% and 25% (TGL 14197 of the GDR). The following weak points of the different cultures were identified: 1. Some batches with a very high content of foreign seeds in the case of chamomile. 2. Low germination capacity in all years of the investigation in case of valerian. 3. Decreased germination capacity in one third of the samples studied in lemon balm. These results should be the reason for farmers to question the seed quality of medicinal and spice plants on the market and to require information on the purity, germination capacity, thousand-seed-weight and content of foreign seeds from the seed producers and traders. In addition, the results might serve as basis for new discussions on standards in seed production and trading of medicinal and spice plants.