The 64-year-old faces a total of 18 charges, including seven of arranging entry of a person into New Zealand by deception and 10 counts of using a person as a slave.
He has intimated he will defend the charges, yet no formal pleas have yet been entered.
Samu was arrested following a lengthy investigation by Immigration NZ and the police.
Allegations made by victims include not being paid for work completed, having their passports taken, and being subjected to physical assaults and threats.
It is claimed the alleged offending had been ongoing since the 1990s across Hawke's Bay.
The victims also claim that their movements were closely monitored and controlled, and there were restrictions on both where they went and who they had contact with.
Immigration NZ assistant general manager Peter Devoy earlier said the charges were the result of around two years of detailed investigative work by INZ and NZ Police
.
He added that the people running the orchards probably didn't know about the alleged offending.
It's understood this was the fourth time INZ had charged someone with people trafficking, but it is the first time the police had become involved.
Detective Inspector Mike Foster of Eastern District Police earlier said there were 10 alleged victims, who are spread across New Zealand and Samoa. Samu would be the only one to face charges.