exotic pampas ?
Pampus exotic ?
seedlings established in guttering - presumably from planted tussocks along front of building. Looks like this pampas grass from here based on the inflorescence and the curly leaf bases on the roof.
Flowering heads seen just above wire mesh fence.
Pampas Grass is a widespread Pest Plant in Westland - it can form dense, compact clumps which are difficult to eradicate. Not to be confused with NZ Toe-toe which has a more open, drooping head.