Growing or Aging?

Puer tea has "row" and "ripe". "Row" is fermented by natural process and "Ripe" has artificial process by cooking. This puer tea is "row" and the mushroom shape is called "tu cha". Fresh row puer cakes have green color, but you cannot drink yet, because the tastes bitter and sour. The strong taste is getting mild each year. Now the color is changed as dark green, but no longer bitter, even leaving sweet taste in my mouth. Some people say the changes as "growing" or "aging". Not sure which is right for the changes...