Here’s a taxonomist’s nightmare. They call one plant ‘Smooth’ something or other, then another one ‘Hairy’, then some genius decides that they’re really the same species, just that some are hairier than others. So, which is it? Are they called ‘Smooth’ even though some are hairy, or should they be ‘Hairy’ with some smooth ones?
This is especially difficult when you’re trying to find it in a field guide. In any event, this picture is the hairy version of the Smooth Hedgenettle, hence the ‘var hispida‘ in the scientific name.
Look for this member of the mint family in wetter areas.