Once the celery and mint has started to rot they should be ok. You could add it to your usual worm food.

From what I've read citrus is not an acceptable food for worms, however if you keep on reading you will find that some people say it is.

Cheers,
Marshall

worms will take care of any decomposing organic material - fresh citrus is not of interest to them because of the "zest" [d-Limonene], but once the bacteria start in on it, they'll take to it, or to the bacteria anyway, which is their major food source

Bill