Although the scent of flowers generally changes during anthesis, this phenomenon has not been investigated in potted carnations. In this study, we examined the scent emissions of potted carnations using the fragrant Dianthus caryophyllus ‘HINAARARE.’ The plants were maintained under a 12-h light/dark cycle, and immediately after the flowers had opened, scent emissions were investigated at 2-day intervals for 15 days. The predominant scent components detected were isoeugenol, a type of phenylpropanoid/benzenoid, and the sesquiterpene β-caryophyllene. The unique sweet scent of this cultivar is believed to be attributable mainly to these two compounds, along with the fatty acid derivative1-octen-3-ol, which has a relatively low aroma threshold. The total scent emissions were characterized by an apparent diurnal rhythm, being lower during the light period and higher during the dark period. This rhythmicity was mainly associated with the emission of isoeugenol and β-caryophyllene, thereby suggesting that the strength of the scent in potted carnations, as perceived by humans, varies between day and night. In addition, we investigated the relationship between an increase in petal in-rolling, a typical symptom of flower senescence, and scent emission. However, no clear correlation was detected. To the best of our knowledge, this is the first study that has provided evidence of a diurnal rhythm in scent emissions from carnations.