These results support the claims observed by AOSA (2009), in which seeds coloration in the tetrazolium test settles faster at higher temperatures. For this reason, Marcos-Filho et al. (1987) recommend that seeds immersed in tetrazolium solution be placed in a chamber set at temperatures of 30 to 40 ºC. In this study, the best combinations for assessing the viability of S. gardneriana seeds were recorded at temperature 35 °C whereas at 30 °C all combinations of concentrations and periods statistically differed from the germination test.