How can you prove that plant leaves evaporate water?

Plants undergo transpiration – evaporation of water. Not all of the water entering through the root is used, and in the process of transpiration, excess water moves and evaporates through the stems, leaves or flowers (external organs of the plant).
Transpiration “in action” can be seen by doing this experiment: the plants should simply be covered with a jar. And after a while we will observe drops on the bank – this is condensation. He is the result of transpiration.