And the winner is……
The RHS Plant of the Centenary is Geranium Rozanne (‘Gerwat’). It has exquisite violet-blue flowers that last from June to September above mounds of slightly marbled, deep green foliage. The Geranium Rozanne (‘Gerwat’) was chosen from a list of 10 plants, one for each decade the RHS Chelsea Flower Show has been held.
Source: rhs.org.uk