Marlborough wine leaders say rogue contractors are taking advantage of tough economic times to cheat people desperate for work.
Wine Marlborough says some pruners have been paid only $6 an hour, while others have been given cheques that bounced.
The organisation's chairperson, Blair Gibbs, says the instances are not common, but grape growers should be on the lookout for contractors offering cut-price labour.
Mr Gibbs says contractors working under the registered seasonal employers scheme are obliged to comply with strict employment guidelines, and most are doing so.
