Jonathan Westwood’s family have been growing forced rhubarb for generations. Their farms are situated in what has been nicknamed Yorkshire’s ‘Rhubarb Triangle’, and D Westwood & Son produce more than 50 percent of the area’s rhubarb. ‘We’re probably the largest producer of forced rhubarb in the world,’ says Jonathan. ‘There’s a bit produced in Holland, and a bit in Canada, but apart from that there’s not very much produced in the world.’
Rhubarb was originally forced to provide an extra fruit in the winter when fresh fruit was difficult to come by. Purpose-built forcing sheds were first built in Yorkshire in the 1880s, but the practice really came into its own during the First and Second World Wars, when thousands of tons of the plant were produced. Difficulties with shipping meant that there wasn’t much fruit coming in from abroad at this time, so rhubarb was in high demand, and was often mixed with other fruits to bulk up products such as jam. Such was the need that the government in both wars actually went as far as to fix the price of rhubarb. ‘I think it was a good price as well by all accounts,’ Jonathan laughs, ‘They made fortunes during the wars.’ During this period there were around 200 producers of forced rhubarb in the triangle, but now there are just 12.
Growing forced rhubarb is a long process. It can be planted between about September and March, and the plants spend two years growing outside before they are moved into the dark forcing sheds. This can’t happen until around November. ‘Rhubarb has to have a certain amount of cold on it to break its dormancy,’ explains Jonathan. When it is exposed to cold, the plant produces a substance called gibberellins. This means the recent mild winter has caused problems for Jonathan. ‘You can water gibberellic acid onto the roots when they’re in the shed,’ he says, ‘But on a normal sized shed it costs about £500 extra to do that.’
Once the rhubarb is in the sheds, it is mostly left to its own devices. ‘It doesn’t get fed in the sheds at all. It’s just water and heat,’ says Jonathan. The plant is grown in the dark to stop it producing chlorophyll and this makes the plant tall and straight, and the leaves small and yellow. It’s not even safe to turn the lights on for long enough to harvest the plant, so it’s done by flickering candlelight. ‘The leaves can start turning green within an hour or so,’ explains Jonathan. He says forced rhubarb is sweeter and more tender than the outdoor crop. ‘Although you still need quite a lot of sugar to use it really,’ he laughs.