Confidence: I'm as sure as I can be.
Notes: Please forgive a substitute ID which is little different from the previous one, but in view of confusion over these plants, including on iSpot, I feel further precision is needed. This is S. officinale and NOT S. x uplandicum (which which much of the confusion exists) as it has leaves narrowing to the stem (not abruptly contracted) and continuing down to the stem to the next internode, flowers that are rich purple and not with shades of blue, corollas that are only very slightly expanded, almost tubular, as compared with corollas that are narrowly bell-shaped. It is var. officinale (formerly called var. purpureum) as it is purple-flowered. The creamy-white flowered plant is var. ochroleucum. The smaller, more creamy-flowered plant in British fens (7 presumably extending to eastern Europe) is the separate subsp. bohemicum. Alan.