Indigo
Flowers that you oversee are always indigo. You aren't sure why though...
Imagine if every flower you were supposed to oversee was indigo. Indigo everywhere!
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Wait, maybe these flowers are only indigo because there is something wrong with your eyes (あい)! Maybe your eyes are indigo and that's why it's all you see!
Can you imagine having indigo-only seeing eyes? I can. Because of this awesome mnemonic.