Tea, Seaweed, Rosemary

Jimmy Doherty visits one of Kenya's largest tea plantations and discovers that tea comes in multiple grades and flavours, and every batch can be subtly different. Matt Tebbutt dives in Cornwall for the edible seaweed that has started cropping up on supermarket shelves and Kate Quilton heads to Slovenia and Northern Ireland, eager to learn about the increasing use of rosemary in foodstuffs.