Onions are currently more expensive than usual due to a tough growing season and the increased price of fertiliser and diesel.
One retailer says the humble brown onion has gone up 200 percent, and as for the red onion, it's even more expensive.
Stats NZ figures released on Saturday showed fruit and veg prices had jumped 17 percent on this time last year, with food price increases the highest in almost a decade and a half.
Onions New Zealand chief executive James Kuperus told Checkpoint a tough growing season has contributed to the high price of onions.
"It was very dry last December and January, which has led to a decrease in yield."
Supply is tight as New Zealand is at the end of last season's crop, and the new season's crop is about to be harvested, he added.
A decreased yield means onions cost about 72 cents a kilo more than at this time last year, Kuperus said.
Other costs have also gone up and some of this has been passed on, he continued.
"We've had fertiliser prices go up from around $900 a tonne to $2000, so that's doubled; we've had agri-chemicals go up in price, diesel has gone up from 80 cents a litre to around $2 a litre over three years - so these increased inputs are double, sometimes nearly triple."
New Zealand is now self-sufficient in onions, he said.
"We were a net importer of onions until the 1920s when we bred the infamous Pukekohe long keeper and now we're self-sufficient."
That means onions that were harvested in April and May were stored and could still be consumed in November, he said.
"The amazing thing about New Zealand onions is that they can be stored for a long time - it's an incredible product that we grow here and we export around the world."
Early season onions needed to be handpicked because they were a little softer, but the rest of the crop was mechanically harvested, he said.
Although New Zealand is generally self-sufficient in brown onions, some red onions still need to be imported as they don't store as well as their brown counterparts.
Red onions are harder to grow, which is reflected in the higher price - however, New Zealand does export them as well, he said.
RNZ
