There is every indication this week that with the New Year celebrations swiftly over, the high street retailers are back in highly competitive mode, with no shortage of new ideas on show.

I remarked on Tesco’s single Monster Mushroom some weeks ago and now it has been joined by a giant smooth-skinned avocado - being sold loose at £1.49 each. Apart from the PLU number, the source and variety was undisclosed, but what was of interest was the label, which read: “When ripe my skin turns from green to black”. There’s nothing like a bit of consumer education in the bid for a unique selling point.

Size, of course, is relative, but I wonder if there is an unofficial definition as to where you draw a line between a large courgette and a marrow. In one supermarket there where two different lines: one, a pale, tender sample no more than four inches long, and on the same shelf a dark green equivalent nearly three times the size.

Different colours and shapes are obviously a great benefit when trying to show fruit and vegetables off to the best, eye-catching advantage, and while most salad lines are predominately green, I came across something different in Sainsbury’s Taste the Difference range for a modest 54p: purple radish seedlings. In this case they are being grown by Peter Walls in West Sussex, and are a far cry from the traditional seedling offers, mustard and cress.

Meanwhile, the depth of description that abounds in the baby-leaf and pre-packed salad categories never ceases to amaze. Tesco has now added French and Italian salads, while its watercress, spinach and rocket pack, priced at £1.79, emphasises its freshness by carrying the sticker proclaiming it is “chilled within two hours of leaving the field”.

And things are stirring in the fruit section as well. While there may still be some controversy over labelling for Pink Lady, or should I say, Cripps Pink, Marks & Spencer is taking no chances with the grape variety trademarked Absolutely Pink grown in Namibia on a half-price ticket for £2.99.

The upmarket retailer has also added a new dimension to cut fruit, with a 375g Layered Tropical Rainbow salad pack priced at £3.99. Interestingly, it breaks with the convention of both pouch packs and sealed flat trays, and certainly displays the shapes and colours far better.

On the citrus front, there also seems to be a surge in grapefruit with M&S putting out the fruit in its special bumper bins and using a sales slogan associated with rainbows, which should delight the FPC. And Waitrose, not wanting to be outdone, is giving away a healthy-eating and diet guide as part of a promotion on its large, netted fruit offerings.