It's hard to say exactly when the crops will regrow (if they have truly failed) or what will happen if you continue on your current course. We have seen reports of crop failure, and the farm is being examined for the v1.1 update to make sure it produces reliably. One thing you might try is to pause your game for at least a few hours. The game doesn't differentiate between paused and unpaused states for certain aspects of the game, which could work to your advantage. When the game is paused, your villagers don't age, don't eat, and don't work. BUT, the farm may not be aware of being in pause and the crops could regrow. I haven't tested that in v1.0, but it's worth a shot.