World's most expensive pineapple grown in Cornwall

It measures just six inches from top to toe; measly by pineapple standards. But for those concerned about food miles, this particular ananas comusus will have extra credibility: it was grown in Cornwall in a glasshouse heated by horse manure.

The tiny fruit was cultivated in the pineapple pit at the Lost Gardens of Heligan, near the south coast village of Mevagissey. It may be half the size of the average supermarket pineapple but it carries an estimated price tag of £10,000, which covers labour costs, equipment – and urine-soaked hay.

"It's a really small fruit but the irony is, it must be the most expensive pineapple in the world," said Nicola Bradley, supervisor at the productive gardens. "We were so excited about it; so much hard work and hard labour has gone into it. We shared it round the gardeners and it was delicious."

Heligan's pineapple pit, which is around 40ft long and consists of three 4ft-deep trenches, fell into disuse at the start of the First World War. It was rediscovered and renovated in 1993. Heated through glass light in the summer, the pit relies on 30 tonnes of decomposing hay, which is soaked in horse urine and refreshed three or four times during the winter months to help it reach the right growing temperature. Ms Bradley said the temperature had to be at least 11C and the optimum was 24C.

Heligan's gardeners hope to add to the 40 plants currently housed in the pit, and expect more regular crops in coming years because of a better supply of manure. In future, they are hoping to spray their hay with artificial nitrogen fertilisers instead of urine.

The "hotbed" system is thought to date back to the time of Charles II but with the advent of steam boats in the mid-19th century, it fell into disuse, as importing the fruit from the Americas became more viable.