In 2006, potatoes cost $1.10 a kilo - that had risen to $2.10 in September this year.
Potato prices hit a 10-year high of $2.25 a kilo in January this year.
Potatoes New Zealand chief executive Chris Claridge said last week that potato farmers we're about 20 per cent behind on planting across the country because of wet weather.
Chris Claridge: "About 15 per cent of the total crop goes into crisping and we've got some shortfalls until the new season crisping potatoes become available to the processors – they should start to get supply around about January [or] February."
Potatoes are an $810 million industry according to Potatoes NZ, covering about 510,000 hectares of land.
About half are for chips, 35 per cent whole potatoes bought in stores, and 15 per cent go into crisps.
Spokesman Steve Sheppard said 73 per cent of potatoes were grown in Pukekohe, which had recently experienced unseasonable weather.
The Manawatu-Kapiti area was also a hub for potatoes but the region had experienced 25 per cent more rainfall than an average, and the most rain for September in 17 years, he said.
