Never heard of it. Until now. Several interesting ideas. We live and learn. It's not that straightforward - several plants seem to go by this name. Wants a bit of time to research it. Nymphaea Caerulea looks like the thing. It could be the source for Homer's Lotus Eaters.
Nelumbo nucifera is related and has similar properties.
I doubt that it would thrive this far north of the Nile, however. The Tyne's chilly in winter.