Guyu

The traditional Chinese lunisolar calendar divide a year into 24 solar terms. Gǔyǔ, "Kokuu", "Gogu", or "Cốc vũ" is the 6th solar term. It begins when the Sun reaches the celestial longitude of 30° and ends when it reaches the longitude of 45°. It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 30°. In the Gregorian calendar, it usually begins around April 20 and ends around May 5.
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 Guyu include: