But the best buy for tomatoes was at the Parnell market, at $8 kg, while our greengrocers' tomato prices were better than supermarkets.
Lettuces were also easier on the wallet at the market stall - but supermarkets could not be beaten on price for broccoli, with Pak 'N Save's rate of $1.89 a head the cheapest.
Asked where the cheapest produce could generally be found, Horticulture New Zealand chief executive Peter Silcock guessed at farmer's markets.
"When you look at the fact that the farmer is selling his own product, then certainly you're cutting out the wholesaler."
But items could cost less at supermarkets when there was ample stock or at times of over-supply.
"The grower going through a supermarket or grocer may be paid less than the actual cost of production, but if a farmer is selling something at a farmer's market, he's not likely to sell something less than the cost of production."
He said recent publicity about the high cost of fruit and vegetables tended to concentrate on summer salad ingredients, such as tomatoes, capsicum and lettuce, which were out of season.
Most shoppers adjusted their buying habits to take advantage of cheap seasonal produce, such as apples, kiwifruit and kumara.
Food and Grocery Council chief executive Katherine Rich said shopping at a farmer's market could feel like a "great experience" - but she questioned whether there was any difference in quality or price.
"When I've visited farmer's markets from time to time, I haven't seen a great difference in price. Supermarkets also have very stringent guidelines about the quality of products, so there's greater uniformity - and they will be of a higher standard."
But Parnell Farmer's Market manager Gill Warren believed market produce was fresher with more taste.
"It lasts so much longer in your fridge. Fewer people have handled it, so things aren't so bruised."