Pukekohe vegetable growers are warning COVID-19 checkpoints in their area could slow the flow of produce to supermarkets and other retailers.
The large vegetable production area is close to the Auckland-Waikato border, with some market gardens split between both regions.
Pukekohe Vegetable Growers Association's president Kylie Faulkner said staff were struggling to move between level 3 and level 2 COVID-19 restriction zones to complete essential work like harvesting crops.
"We are hearing growers in the Tūākau and the Pukekohe areas are having waits of up to one to two hours to get through checkpoints, causing quite a disruption to production," she said.
Faulkner said it also needed to be clarified exactly what documentation essential workers were required to carry and whether this could be in a digital format.
"In our own business we had some of our staff trying to move from level 2 into level 3 this morning for work and they were turned away, because they didn't have the official [exemption] letter printed out," she said.
Faulkner said growers didn't want the COVID-19 level 3 boundary running directly through a major horticultural production area.
But if that couldn't be changed, it would be good for freight lanes on roads to be used to speed up wait times at checkpoints, she said.
Brendan Balle of the Pukekohe-based market garden business, Balle Brothers, agreed the current system wasn't manageable for growers and it needed to change.
Balle said some staff had to shift themselves, as well as farm machinery, between the Auckland and Waikato boundary several times a day.
"The boundary area has been arbitrarily set half way through the Pukekohe production area and that is where the main problem is ... so we're finding that very disruptive for getting crops harvested, getting food to the supermarkets and whatever other channels that are allowed to be open.
"If it carries on like it is, I think that the supermarkets and any other retail outlets for fresh fruit and vegetables will need to be notified that there is likely to be some disruption to supply."
In a statement, the Ministry for Primary Industries said it was keeping in touch with food producers to ensure their workers were safe and vital production continued.
It said travel exemptions granted by the Ministry of Health for key workers involved in dairy processing and horticulture production and distribution should help to smooth the path for travel in and out of Auckland for work.