Different cultures view blending tea differently.
The art of infusing teas and herbs is as ancient as the drink itself. Tribes have their own tradition of blending tea and spices with indigenous herbs. A medicine woman or chief may have their own secret concoctions. A Japanese Zen Priest may have a strict ceremony to follow in how they mix teas that may be contrary to a neighboring Zen Priest. In Europe tea blending changes with each language. The German fashion of using strong Darjeeling tea may be different from the Morrocan mints infused in the region of Andalusia Spain
How does one blend?
For thousands of years tea connoisseurs have infused teas with botanical medicine. Safe blending is done through experimentation and can be done in your own kitchen and garden.
https://www.youtube.com/watch?v=Ru4zSf6FXMk