Chunfen

The traditional Chinese calendar divides a year into 24 solar terms.
Chūnfēn, "Shunbun", "Chunbun", or "Xuân phân" is the 4th solar term. It begins when the Sun reaches the celestial longitude of 0° and ends when it reaches the longitude of 15°. In the Gregorian calendar, it usually begins around 20 March and ends around 4 April (5 April East Asia time). It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 0°.
Pentads.
Each solar term can be divided into 3 pentads (候). They are: first pentad (初候), second pentad (次候) and last pentad (末候). Pentads in Chunfen include:
A pentad as follows was referred to Japanese traditional calendar presented in a smaller, easy to use, format.