The Flower menu is a menu type.
How to Get This Menu
Simply interact with the Flower Girl deep in the Plant Labyrinth (Past) rooms. Make sure you do not kill the flower girl in the Plant Labyrinth either, otherwise this Flower girl will be dead and will not grant you the menu.
Best way to get this Menu
Go to the Mouths and eyes world and through the hands teleporter. make it too the Footprint Path and agitate the bottom most box of red tentacles until they envelop Sabitsuki and take you to the alternate footprint path with a calm Kaibutsu. Go through the Red entrance and through the tentacle path and you will be in the Plant Labyrinth (Past) rooms with hospital children that have plants growing on them.
Make your way down to the middle section and enter the room and interact with the girl in between two heartbeat monitors and you will receive the menu.