He needed a near two-week hospital stay to recover from the four stab wounds - one of which punctured his lung. He forgave her after she apologised.
Judge Moala's start point for the sentence started at six years and eight months' imprisonment, before the discounts were applied.
The Solicitor-General appealed the sentence to the High Court at Auckland, arguing the cultural discount was too high.
Counsel for the Solicitor-General said an argument could be made for a 30 per cent discount for hardship in her case because of the needs to recognise Maori pot-colonial experience but cited a previous decision which said "cultural norms cannot excuse that conduct for some groups but not for others".
"I agree with the Solicitor-General that Ms Heta's 'difficult upbringing' could not by itself attract a discount of 30 per cent in addition to a discount of 10 per cent for participation in the restorative justice process," the appeal judge, Justice Christian Whata, said.
"That is outside the range normally afforded for these factors where no linkages are drawn to moral culpability."
However, Justice Whata said, it was not accepted the personal mitigating factors identified were limited to those two factors.
Alcohol abuse, lack of positive whānau and other pro-social influences early in life and "significant strides" towards rehabilitation were among other factors considered, he said.
Justice Whata said Judge Moala, in addressing the cultural report, observed Heta's life reflected the "significant post-colonial trauma and disruption of the cultural identity experienced by Māori whānau, hapu and iwi".
"Alcohol and poverty has resulted in offending of this type," he said
"[Judge Moala] noted that Ms Heta has lived a life that has involved drinking, physical and emotional violence that controlled her from childhood into her adulthood."
Justice Whata also noted high incarceration rates in the Māori population.
"The effects of colonisation on Māori communities are well documented," he said.
"Loss of land and other tribal resources together with the destruction of traditional social structures, tikanga, culture and language preceded widescale migration from tribal rohe to urban areas.
"For every generation since, Māori have been disproportionately represented among the poorest, most illiterate and most criminalised in New Zealand."
Justice Whata dismissed the appeal yesterday, ruling Judge Moala's sentence was not manifestly inadequate.
