This have happened if u have been messing with the date or time on ur iPhone / iPod as
this happened to me and I just deleted the frozen crops and plowed the land and started
over again - hope this helped!!

if thats true why does it happen to some people but not others?

its because some people are coooooooooool and others arn't

What if that does not work

The same thing happened 2 me

I messed with the time and date a few times and the first few times it didn't freeze but
after I went past midnight my crops would no longer progress! Finally I figured it out
(after deleting my crops)...move the day forward after u pass midnight...the ipod wont do
it on its own...works perfectly!

-Adele