Having said there were no blue scarlet pimpernels at Wimpole Richard Brown (from Emorsgate seeds) informed me that, when he was collecting some hairy St John’s wort from Wimpole with my permission, he came across a patch of the blue form of scarlet pimpernel in 2012. Below is a section taken from Wiki:
‘Scarlet pimpernel has weak sprawling stems growing to about 50 cm (20 in) long, which bear bright green ovate sessile leaves in opposite pairs. The small orange, red or blue flowers are produced in the leaf axils from spring to autumn. The petal margins are somewhat crenate and have small glandular hairs. Blue-flowered plants (A. arvensis Forma azurea) are common in some areas, such as the Mediterranean region, and should not be confused with the related Blue pimpernel, Anagallis foemina, sometimes ssp. foemina. In 2007, a molecular phylogenetic study showed that Anagallis foemina is more closely related to Anagallis monelli than to Anagallis arvensis, and should be treated as a separate species. Scarlet pimpernel flowers are open only when the sun shines.’
Also seen in the photograph is the broad leaved fluellen.