She has been humming so long, her friends think it is "normal" behaviour.
"I’m just known as the hummer."
But on Saturday night, the 13-year-old got to use her full voice in front of her biggest audience yet.
She sang the New Zealand and Australian national anthems for about 15,000 rugby fans at Forsyth Barr Stadium and tens of thousands more on television, before the Highlanders versus Crusaders Anzac match.
Poppy said she had always dreamt of singing in front of a large audience, but never thought it would be that big.
"This is my biggest crowd yet.
"I was a little bit nervous about it.
"I'm not normally the nervous type, really."
She said it was not like singing in the bathroom.
"But the music started and I just got on with it."
With that kind of public exposure, surely she will now be known as "the singer".
She has been singing for the past six years at The Voice Lab, under tutor Kelly Hocking.
As well as singing, Poppy also does tap dancing, jazz dance, musical theatre and hip-hop.
While it was still a long way off, the year 9 Columba College student hoped to study music at university before forging a professional career.
Like most young teens, she dreams of becoming a famous pop star, and writing and recording her own music.
And she is already achieving some of those dreams.
She has recorded a song which is on Spotify, and she has performed flawlessly in front of a massive crowd.
Poppy hoped her recent performance would be another step towards the next item on her list of dreams to tick off — singing the national anthem at an All Blacks game.
"I'd just like to put that message out there to the All Blacks, I'm available for national anthems."
