What is this please?

Shady, neglected end of garden London clay


Doesn't sting or smell

 

Could it be Plectranthus?

 

Will Google. Thanks
Edit:
That would be nice, but I'm not sure the leaves are the same

 

Are the stems square in cross-section?

 

Looks quite dead nettle like but I also see some similarities to geum.

 

Thinking about it again, I agree @Thevictorian

 

Yes @Dovefromabove

 

Looks like Garlic Mustard to me.

 

Should it smell of garlic or mustard? It doesn't.

 

I'm getting a slight whiff of woundwort off the wilting cutting

 

Could be horehound @Loofah Google images make the leaves look a sage colour,though. Is this always the case? These leaves are a brighter green.
Pretty sure it's not geum. not even grim urbanism as predictive text likes to geum urbanum. I prefer that name too.

 

Not, Geum.
Could be Woundwort.

 

That's what I'm thinking, now. Maybe they need hot sun to really stink @Punkdoc

 

A much better name. My regular patrols fighting Grim Urbanism now sound much more interesting