Although Betony (Betonica officinalis) is common in England it is quite rare in Scotland.  It is not dissimilar to Hedge woundwort (extra) and was also regarded as a plant for healing and often planted in physic and monastery gardens.  In past times it was believed to be a herb that was capable of curing forty seven diseases and an old Italian proverb advised anyone who was unwell to “Sell your coat and buy betony.”  All parts of the betony plant are edible and can be used fresh or dried to make a slightly spicy aromatic tea to aid digestion and the circulation as well as help to calm and alleviate symptoms of depression and anxiety, cure headaches and aid concentration.  Modern experiments indicate that poultices made from the leaves have antiseptic qualities.
Unfortunately changes in agricultural practices have contributed to its decline as with many other native flowers, and those that I have found locally are growing in areas untouched by herbicides. 

Edit  gen2 has identified this as Marsh Woundwort so some of the above information may be wrong.