Ground-ivy (Glechoma hederacea) is a type of dead-nettle, common in woodlands, lurking under hedgerows and scrambling over dampish spaces. Richard Mabey’s Flora Britannica tells me this pretty little plant was once known as blue runner because of its blue-ish flowers and its habit of spreading via overground runners. Another interesting titbit: ‘before hops became widely used in brewing, it was once one of the chief bittering agents in the making of beer’, which is why another of its common names is ale-hoof.