Growth Potion or Double Avatar Size is a consumable in FarmVille, released during the Spring Time Event. When a farmer has collected 10 Spring Eggs, they can redeem them for a Mystery Egg. One of the possible contents of that egg is Double Avatar Size. When applied, it enlarges the avatar to its double size, still only taking up an area of 1x1. That way, they can be better seen on a large farm, but do not take more space than before. Once you "drink" the potion, you will stay big for 1 hour.