Hi again - being new to the forum I'm not sure whether I should start a new thread for help with more plant identification or stick with this one.
Have decided to stick with this thread and see if I get any responses.
The following photos of unidentified plant were taken today and a couple of days ago. The plant is perennial and spreads by way of underground roots sending up individual flowering shoots at random !!! It hasn't proved to be invasive yet but I think it could be so, if I don't keep it in check !!
Neither the flowers nor leaves are aromatic. Not sure if it's clear from any of the photos but the shoots are square rather than round which I think is unusual so may help with its identity, or family, at least.
The first photo shows the plant in situ in front of the foxglove and to the left of it. The second shows leaf arrangement and flowers in the bud stage, the third a close up of a flower which puts me in mind of a snapdragon and the final photo is looking down at young emerging shoots showing leaf arrangement.
Thanks to everyone for looking and for any helpful suggestions to explore.