As you grow in Farmville2 game, you need to expand your FarmVille2 farms to hold your animals, trees and croplands and to finish quests early. There are in total 16 Farmland out of which 2 are clear for Farming at the beginning of the game and 1 is cleared while Marie is giving you walk-through of playing FarmVille2, rewarding you with a feed mill and a lemon tree.
Once you the see the sign board as given in the image, it indicate the Farmland is available is to expand which you can do by using the items and certain amount of FarmVille2 Coins. Few Farmlands are locked till you attain certain level of experience. After reaching the desired level you can expand farmlands by fulfilling requirement of various Items and certain amount of FarmVille2 Coins. If you don’t want to wait for collection of items you can get the expansion instantly by using FarmVille2 Bucks.