It really depends on the language, C is easy to learn and takes a lifetime to truly master. C++ is harder to learn, but easier to use effectively sooner. Java is like C++ except easier and it's easier to learn after you learn C++. It all depends on what you already know and what you're willing to put into it. For me it took about three weeks before I really got the hang of C and fell in love with it.
Observations about the nature of programming, how long it took you to learn whatever you learned.