Although labeled H. 'Coerulea', it appears
that this plant is actually Hosta caerulea latifolia
which is synonymous with
Hosta sieboldiana sieboldiana... is that clear? In the end, I think it means
that it is a big blue-green hosta of the 'Sieboldiana'-type.
BTW
- Coerulea is a Latin word for blue.