Rogation Days (of Prayer and Fasting)

"Rogation Days" In Catholic Encyclopedia: https://www.newadvent.org/cathen/13110b.htm

Days of prayer, and formerly also of fasting, instituted by the Church to appease God's anger at man's transgressions, to ask protection in calamities, and to obtain a good and bountiful harvest

The Rogation Days are the 25th of April, called Major, and the three days before the feast of the Ascension, called Minor.