Increased sales at Waitrose as a result of its tie up with Delia Smith and Heston Blumenthal have continued with another strong week of trading.

Sales for the week were 7.4% higher than last year for the week ending 19 November. Sales of Delia’s Christmas cake kit are almost double that of last year and its Heston-branded mince pies are performing strongly.

The grocer also attributed its good performance to increased sales of “weather blemished” apples – up 57% week on week.  

Commercial director Mark Williamson said: “The week has been one of green news – with the WWF announcing that Waitrose has achieved a perfect score in its 2011 Palm Oil Scorecard.”

Waitrose opened its store (pictured) with the lowest ever carbon emissions, close to its head office in Bracknell, Berkshire, on Thursday. The shop will have 80% less carbon dioxide equivalent emissions and a host of biodiversity features including a roof covered with grass for wildlife.

From next year, all new Waitrose shops and major refurbishments will incorporate a biodiversity action plan.