The portland rose is the result of a cross between the damask and china roses.
Autum damask and slater's crimson china are known as the forerunner of the first portland roses found near Paestum, Italy.
His own name was given by the plant collector, Margaret Cavendish Bentinck, of which he was the Duchesse of Portland in the 1780s.
He is a collector of various things, one of which is a collector of roses.