There is tea grown in the UK! Recently found out(after the Yorkshire tea), tea gardens (why not a plantation) are in Cornwall, Wales and Scotland too. They sell enough to be commercially viable!
Still love the story of how tea was found by a leaf falling in to a cup of hot water.
An ex-collegue of mine whose wife was Chinese used to lose his shit if you ever said tea was English.
It was great sport to ask if anyone had a Yorkshire tea bag spare.