Retailers and suppliers are anticipating a short-lived boost in fresh produce sales this month on the back of strong December figures as consumers undertake healthy eating drives after the excesses of Christmas.

Major veg and salads supplier The Greenery said that it was prepared for higher sales through the first three weeks of January. The company scheduled harvesting of salad vegetables over Christmas so they could be brought to store immediately after the holidays.

"The first week after Christmas always sees a huge rise in salad sales," said Greenery UK chief executive Martin Brown. "If it is a result of new year resolutions, these appear not to last long because within three weeks sales are back at the average winter level."

In the first week of January last year The Greenery supplied more than 20% above its average weekly winter volume of tomatoes and cucumbers.

James Hallett of MW Mack also predicted a sharp sales uplift, though he was not convinced healthy eating was the mey driver. "January sales are generally quite strong, but it's difficult to extrapolate if that is just because stores are restocking after the Christmas," he said.

A number of retailers have already reported above-expectation fresh produce sales over Christmas. Waitrose said vegetable sales were particularly strong, with seasonal lines doing well. Red cabbage exceeded expectations, 63% up year-on-year, while sales of sprouts on stalks were 51% up.

Another notable performer was Maris Piper potatoes, with 2.5kg bags selling five times more than during a week in November, making them the retailer's best individual selling line of prepacked potatoes.

Asda said sales of loose veg such as sprouts and parsnips were higher than in previous years, with loose sprouts up 47% against last Christmas.