Chiltern Seeds say: "Once a fairly common plant to be found growing on sand and shingle around the coasts of these Islands, it has now become a good deal rarer thanks to the demand for its young, white stems as an Asparagus-like delicacy. A splendid plant with large and very fleshy, very glaucous, wavy, long-stalked, ornamental leaves, and bearing in summer large panicles of rather attractive, veined white flowers which have a delicious honey-like smell. Hardy throughout the British Isles. 1-2 ft."
I'm not quite sure where this plant came from but I think Charlie had something to do with it!