Two different gynostemma teas taste completely different, why? So i've ordered 2 different brands of gynostemma (or jiaogulan in chinese) and they each taste very differently. The first one I've ordered tastes extremely bitter, the second one I've ordered tastes light and sweet, even though I can detect somewhat of a similar bitter after taste.

According to the boxes they are both 100% gynostemma leaf, and the tea bags appear to be exactly the same in size. Why does one taste very bitter why the other one doesn't? Is it possible the leaves from the first box were older when i ordered them?
If they come from 2 different brands, there can be many reason why they taste different.

Could be harvested from different areas; picked at different time/season and/or mishandled.

Could have been badly stored and packaged.