Flowers are usually eight tiles. An American card line often needs them.
On a Chinese table a flower is usually exposed and replaced. In American play it stays in the hand and follows the printed line.
A flower is not a joker.
The same word, a different job
On an American card, flowers are often a group in the line, and a joker may help. In MCR, flowers score and you draw a replacement. Riichi has no flowers.
Flowers are not jokers. Flowers may pass in the Charleston; jokers may not. Separate them when you name the tiles.