"Forgot, absolutely forgot to do it."
She admitted the city's sole tree was "a bit sad" and she wanted a new one next year.
The lack of Christmas cheer has been grumpily noted by residents.
Catherine Barker posted on the Nelson City Council Facebook page: "What the hell NCC... where are our Christmas decorations? Where's your Christmas spirit?"
The council replied it had put up "stunning hanging baskets" and Christmas banners throughout the central city.
But it admitted new decorations hadn't been budgeted for.
"Additional decorations had not been budgeted for this year as retail stores normally dress their own windows in a Christmas fashion. The Mayor is proposing budget for next year."
The town isn't entirely without festivities, however, with Uniquely Nelson receiving council money for Christmas elves in the central city.
The elves visited The Nelson Community Art Works for their annual Christmas Party!
Posted by Uniquely Nelson on Thursday, 15 December 2016