Queen Mary with RHS official at the RHS Chelsea Flower Show

The RHS Chelsea Flower Show, also known as the Great Spring Show, is held for five days in May by the Royal Horticultural Society (RHS) in the grounds of the Royal Hospital Chelsea in London. Held annually at Chelsea since 1913 (apart from gaps during the two World Wars), it is the most famous flower and landscape gardens show in the United Kingdom, if not the world.