When you go away on holiday your worm farm will survive quite happily for an extended period without you.
Cut a butternut in half and put this in the worm farm flesh side down, this will keep your worms fed and happy for many weeks. Make sure you move the farm into a protected place to prevent it from getting too hot or cold.
Also make sure that the top of the food is well covered with damp bedding, shredded paper will do a great job of keeping your worms nice and moist.
While you are on holiday the worms will survive for up to three weeks without an issue.
When you return simply resume your normal feeding routine.