Election returns show Bowker's company also donated $5000 to her Mt Albert campaign in 2017, before she became Labour leader. Candidates have to disclose donations of more than $1500.
Ardern said today that she had not remembered the donation when the Nash issue was raised with her, or made the link between Bowker and Caniwi.
She said she did some due diligence on the people and companies she took money from, and no red flags were raised at the time. "That indicates I did not know Bowker or any of his views that I am subsequently aware of."
She said she could not speculate as to why he had chosen to give the donation and she would not take any more from him if offered.
Asked if she would return the money, she said it was spent on the byelection in which she was successful: "I imagine Mr Bowker is probably quite unhappy with the outcome of his donation."
In the past, Bowker has also donated to New Zealand First and Act.
Bowker was a critic of Labour's former policy of a capital gains tax, and has been critical of the changes Labour has made on the bright-line test and tax deductibility for investment properties.
He said last week that he was giving up his co-ownership of the Hurricanes rugby franchise, but said that was due to a restructure rather than the reaction to his comments.
He stood by the comments he had made and his right to make them, saying they were not racist.
He also questioned whether Ardern would be "willing to comment on whether my remarks would be considered Hate Speech, prosecutable under the proposed legislation?"
Ardern said today that she did not consider the comments to be hate speech, "Just something that many people, myself included, found pretty appalling and backward."
In response to Bowker's comments, Mallard said he would boycott Hurricanes games until Bowker was no longer involved.
Robertson also weighed in, calling the comments "appalling" and he was also considering a boycott.
Hurricanes player TJ Perenara described the comments as insulting and "underlying racism".
Act leader David Seymour questioned whether it would fall foul of proposed changes to the hate speech law, saying it remained unclear whether political speech would be sanctioned under that law.