Watermelons come in a vast range of sizes and shapes. As if to prove the point, a recent TV advertisement by Sainsbury’s, showcasing its total range on sale for half price, featured a child enjoying a fruit which must have weighed several kilos.

Having a range from small cannonballs to boat-shaped giants means this is not one of the easiest products to display.

However, the hot weather has generated interest in the fresh-cut range, homing in on convenience for potential customers who prefer to sit at home rather than take the complete product to the beach.

There are now several packs of chunks on the shelves, although Marks & Spencer has gone one step further with mixed wedges at £2.99. As well as the well-known green skinned, red flesh variety, it is also including the yellow alternative.

Other lines that vary enormously in size include courgettes, which as autumn is not far away can look like small marrows. When it comes to purple aubergines, however, the smallest finger size I have seen yet were being sold loose in Morrisons. More intriguingly, the

£1.50/lb products came from India.

France, a lesser known source in the UK for mushrooms, appeared in the same store under the retailer’s Best brand. Its shiitaki, at £1.39/100g, are well known, and probably now top of the list of strange-sounding products in the exotic veg range.

They may originate from the Far East, but many varieties are grown in the UK. Well-known specialist Livesey Bros, which farms in Leicester, is an example of how to find and develop a niche market.

The firm has recently given the five varieties in its Japanese range a packaging makeover switching from clear bags to something far smarter and easier for consumers to read.

It has also introduced English names, with Brown Beech far easier to manage than Buna Shimeji.

Keeping things simple is always a good idea, although the perception of how produce is used and prepared can be changed.

Tesco has come up with a new Baby Leaf Greens pack - the nomenclature more usually associated with prepared salad - on special offer at 78p for 200g.