How long have lotus flowers been in this pond?
A lotus flower is a lotus flower!
This is a jukugo word that uses the on'yomi readings of the kanji. You didn't learn this reading for 花 yet, so here's a mnemonic to help you:
Something is on the lotus flower... something little and kinda shiny. It's a little gecko (げ). It's hiding in the lotus and trying to catch flies. How cute!