This is a very bright (and very big!) elephant ear which is called 'Lime Zinger' because of it's bright chartreuse coloring.
These will grow to be quite large, and are often used as accent landscape plants, and make quite a statement in any situation. They like bright light, but not in the afternoon, when the sun is hottest- they can be burned at that time of day, so shade should be provided at that time of day. They like evenly moist, but well draining soil.