Not to sour you on the topic (haha) but the lemon tree can ONLY be won in the Mystery Box. (Please know that anyone who claims they can get you a lemon tree can only achieve this by a hack)
The sweet thing about the lemon tree is it’s another item that provides cash for your town! Every 6 hours the game hands you a basket of lemons and when you click on them they turn to cash!
When the game first came out if you saw a lemon tree in a friends’ town you could steal it from them and plant it in your Springfield. Then, after 24 hours any of your friends could steal it from you!
However, with the October 2012 update the ability to steal the lemon tree was disabled. EA describes this as a glitch and say that they hope to get this ability restored in the future.
Have you been lucky enough to get the elusive Lemon Tree?