BBC:

Every detail inside the out-of-time barn carried hidden meaning. There were flickering candles elevated on spikes, all thinly spread out to help workers navigate the blackness without fear of treading on the prized crop. There were shadowy hoes propped against the brick walls to help mulch the earth. There was the outline of gas propane heaters, and a sprinkler system to intensify the heat and humidity in the dark. There were around half a million buds – all cultivated in rows and all making groaning sounds as they germinated at an unnatural speed. It was a riveting exhibition of Mother Nature at work, yet a display teetering on the edge of the surreal. And one all-the-more glorious for rarely being seen by outsiders.

Come to West Yorkshire during the rhubarb harvest in mid-winter and you can expect to hear tales of this strange agricultural ritual. Here, land gathers into a swathe of greenbelt that points to the cities of Bradford, Leeds and Wakefield. Some 23 sq km in area, the realm is punctuated by the odd cathedral and castle and framed by plunging dales to the north and the gently sloping foothills of the Pennines to the west. But it is also a pocket of frozen, flinty soil with high rainfall where one of the world’s most complex vegetables grows in abundance. And it would be a peculiar place even without the name ‘the Rhubarb Triangle’. …

“Rhubarb has been called ‘God’s great gift’,” said Oldroyd Hulme, who is also known as the ‘high priestess of rhubarb’ for her knowledge on the subject. “Watch and you can see the plants shooting towards the light – just as we would warm our hands on a fire.”

A notoriously fickle vegetable to harvest, Yorkshire forced rhubarb is anything but easy to grow. It thrives in the county’s cold winters, but if the soil is too wet, it can’t be planted. If the temperature is too hot, it won’t grow; and 10 or more frosts are needed before a farmer can even think about forcing it. Only then can horticulturalists remove the heavy roots from the field, then clean and replant them inside the forcing sheds where photosynthesis is limited, encouraging glucose stored in the roots to stimulate growth. It demands patience, expertise and good fortune, and, ultimately, it is engineered for maximum taste: once deprived of light, the vegetable is forced to use the energy stored in its roots, making it far sweeter than the normal variety.

RTWT