The particularly low germination percentage recorded for S. retroflexum could be due to the inherent dormancy problems of nightshades, which are exacerbated by harvesting and processing methods that fail to adequately remove the sugars and germination inhibitors present in the fruit during the extraction of the seed ( Abukutsa-Onyango, 2007). In this study, S. retroflexum emerged optimally at 20 °C, which was within the optimal growth range of most Solanaceae (Edmonds and Chweya, 1997). Use of pre-sowing treatments and/or extended storage periods, aimed at releasing seed from dormancy, could assist the development of a better understanding of the germination of this species.