The spiritual interpretation of dew in a dream comes from its long-standing association with divinity and the purifying aspect of the rain that falls from heaven. The rain is said to be an elixir that renews life because it is so fresh and clean, as dew.
The meaning of dew on leaves in your dream can be determined by the feelings and thoughts wrapped up in your interpretation. To a lot of people, dew on leaves can signify the elixir of life. It is somehow like waking up to a ready-made day. You might feel rejuvenated or refreshed after seeing dew in your dream.