Question: are limes not ripe lemons?
Answer: Limes are picked when they are fully grown, but still green and unripe. If Limes are allowed to fully ripen on the tree, they actually turn from green to yellow. Because of this, some people believe (erroneously) that Limes are just unripe Lemons. Whereas, truth to tell, even the Lemons that we buy are unripe Lemons.