The amount of potatoes in store in January reached a record 2.4million tonnes, according to AHDB Potatoes.
Data from the levy body revealed January stocks were up 25%, or 492,000 tonnes, on the year before.
Drawdown rates were also at their highest level since 2010 – the year AHDB began measuring stock – with growers drawing down 1.19million tonnes of tatties between November 2017 and January.
This is 226,000 tonnes more than the same period last season and 14% higher than the five-year average.
AHDB analyst Peter Collier said data from Kantar Worldpanel revealed that retail sales of fresh potatoes were up 3.6% in the three-month period to the end of January.
“While this is good news, it does not entirely explain the increase in drawdown rate,” said Mr Collier.
“Another factor is a greater level of grade- outs in this year’s crop. With quality reported as reduced in 2017/18, there has been an increased tonnage requirement to meet specifications, as seen by reports of a higher ‘out grade’ percentage than usual.”
He said delays to starting planting this year’s crop could have an impact on the market for last season’s stocks sitting in storage.
“The delayed, wet start to 2018/19 earlies planting could see this marketing season extended, causing a tightening of supplies before the new crop is lifted,” added Mr Collier. “Conditions can change quickly, so I would recommend keeping an eye on Potato Data Centre, or our newsletter Potato Weekly, for more information.”