Most notions of the seasons in works of ancient Indian medicine list frost, spring, summer, rainy season, autumn and winter as the particular times of the year. However, in some contexts, the hibernal season frost (śiśira) is left out and replaced by a second rainy season, called beginning of the rain (prāvṛṣ) and placed between summer and the actual rainy season. In this paper, I firstly introduce the concept of the seasons and the division of the year into two halves. Secondly, I examine the dichotomy of two seasonal schemes inside one scientific corpus, which varies regarding the included seasons. Concerning this matter, I follow the investigations of Francis Zimmermann in order to prove that the two schemes are utilized both intentionally and systematically in specific contexts. The two seasonal schemes serve diverse cases, being of use for the physician in different aspects of his work.