Ceremony flowers - Eshikibana

...Although it is also used simply to mean a Buddhist ceremony, such as Kegon-eshiki and Kanjo-eshiki, the term has come to refer primarily to the memorial service held at Nichiren sect temples on the anniversary of Nichiren's death (October 13th). Attending an Oeshiki is called an eishiki mairi, and the cherry blossoms made of Yoshino paper that believers decorate their Buddhist altars on this day are called eishiki flowers. It is said that the Higan cherry blossoms bloom wildly around this time, and these are called eishiki cherry blossoms....

*Some of the terminology that refers to "ceremonial flowers" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…華厳会式，灌頂会式などと，たんに法会の意味でも用いられているが，後世もっぱら日蓮の正忌日(10月13日)に日蓮宗各寺で行われる追恩の法会を指して御会式（おえしき）という。御会式に参ることを会式参りといい，信徒がこの日仏壇に飾る吉野紙製の桜花を会式花という。このころ彼岸桜が狂い咲くといい，これを会式桜と称している。…

※「会式花」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報