Anytime!
And yes, it will take lots of patience, but things you can do are to try and hand feed them their veggies, talk to them in a quieter, higher pitched voice and they will eventualy get used to you. Also, let them come to you, instead of chasing them around the cage to trying and pet them. Always make slower movements too.
My pig Chauncey used to be terribely shy, would never let you get near him, always hiding, but after doing all of what I just told you one day he randomly became more outgoing. It was amazing, but it does take time.