This famous group of rhododendrons was created by Sir Edmund Loder around 1900 by crossing the two fragrant species R. fortunei ssp. fortunei x R. griffithianum. The resulting seedlings were perceived to be so good, more than 35 of them were named. They all grow large, 8ft - 10ft tall in 10 years, but will over time be larger than a house. This cultivar 'Superlative' has fragrant white flowers with a slight pink blush. The most famous of the grex is 'Loderi King George', but one would find it hard to differentiate LKG from 'Superlative'. Hardy to zone 7. Very hard to root, thus the catagory is 'rare'.