British strawberries have long been the harbinger of our brief midsummer. Sadly, like summer itself, their season is short.
Or used to be - because surprisingly, Scottish as well as English strawberries will be springing up until late October, doubling the length of the season of bygone years. And in the colder north, growers have Israeli scientists to thank for this extended growing season.
"Israeli breeding programmes have revolutionised the market for Scottish berry growers," says John Laird of Cairnie Fruit Farm in Fife, nipping off samples of the Ava Rosa variety he grows in polytunnels.
"We used to be so limited up here, compared with southern growers, by rain and early frosts, but now we have plants which are so vigorous, they just keep giving."
Laird buys his Ava Rosa plants from Angus Soft Fruits in north-east Scotland, the result of a joint venture with Tel Aviv grower Efi Izzak dating back to 2001.
"The company in Israel produced 120,000 potential cross-breeds of which we selected Ava in 2003," says ASF's commercial director, John Gray.
He says Ava Rosa, the next generation berry they are now marketing, is loved by customers for both its sweetness and its long shelf life. "Growing in polytunnels does not affect the sweetness of the variety, which is not related to direct sunlight," he explains.
"The tunnels are there to protect the berries from rain, given the harsh realities of our climate."
Gray says 800 tons of Ava Rosa, which are distinguished by their distinctive heart shape, have been produced this year in response to demand - double last year's crop - and that the final pick at the end of September should be on the shelves through October in Sainsbury's, Morrisons and Asda.
Scotland is not the only part of the world to benefit from Israel's pioneering development of weather-resistant strawberry plants, which are becoming a major export.
"This particular programme is not ours, but we have our own breeding programmes in Spain, Ethiopia and Greece," says Efi Yosef, CEO of Yosef's Farm, one of many in Israel which is also developing its own new varieties of strawberry. He explains that the benefits of the new strains Israel is creating for export markets have increased "brix", as the measure of sweetness in the fruit is known, higher yield and better shape as well as taste.
The Rotemi and Sheked varieties Yosef has produced for Greece allow them to be harvested in that country as late as mid-November.
Although he doesn't buy Ava Rosa himself, M&S soft fruit buyer Bill Davies says he is aware of the Israeli "superhero" fruit.
"It's a fine strawberry," he says, adding that any initiative which supports Scottish growers is welcome.
"Because they have a longer, slower growing period, Scottish berries develop more flavour, and there isn't a finer place to get a berry from during July and August.
"There are actually only five months of the year now - November till March - when homegrown strawberries are not in the shops."
The extended berry season - home-grown raspberries will also be in the stores throughout October - is a bonus for Brits as other soft fruits fade away.
Berries are a rich source of Vitamin C, potassium, folic acid and fibre. And strawberries are surprisingly low in sugar, making them the dessert of choice for those trying to control their weight.
Health benefits are driving all berry sales up, says Davies: "People are so aware of how healthy blueberries are that sales have risen massively and taken other berries along with them. Strawberry sales alone are up 10 per cent this year."
However, he admits there may not be awareness of the fact the season has grown so much longer for homegrown fruit.
"We start selling British strawberries in April, and don't stop till the end of November."