Botania version: r1.7-204
Forge version: 10.13.4.1448

You are able to infinitely duplicate Mythical Flowers using the Flower pouch. How that works:
1)Put some flowers in your pouch
2)Open it's gui
3)Press the same button on your keyboard the pouch's slot in the hotbar is
4)The pouch shifts position to the next slot and closes
5)The flowers are both in your slot and in the pouch
6)You can repeat this infinitely

http://postimg.org/image/i5uoa4qgd/ <- a gif image I made to show how exactly that works.