Growing tomatoes naturally in Green Tye

PUBLISHED: 10:49 15 February 2010 | UPDATED: 14:51 20 February 2013

John and Caroline Jones

John and Caroline Jones

John and Caroline Jones show how keeping it simple has led to their success story

GROWING tomatoes commercially requires a considerable amount of energy to heat the greenhouses overnight and during the colder months. John and Caroline Jones, who run Guy and Wright Tomato nurseries in Green Tye near Much Hadham, were finalising their plans at the turn of the millennium to lease a large natural gas generator to heat hot water for their greenhouses, as well as produce electricity. Talking to me at the nurseries Caroline explained that with only three acres such a large investment was not an easy decision: 'Just as we were finalising the details electricity prices crashed and suddenly the larger generators were no longer viable.'

Undeterred the couple researched alternatives, eventually importing five micro turbines from Sweden. Also running on natural gas the turbines produce enough power for 400 homes, so once the couple's heating and electricity needs are met any excess electricity is fed back into the National Grid, providing an extra source of income. In a remarkable symbiosis the waste carbon dioxide produced by the micro turbines is routed to the greenhouses, where a carbon dioxide rich atmosphere suits the growing tomato plants down to the ground. Cleverly converting the carbon dioxide to oxygen naturally, via photosynthesis, ensures the carbon dioxide also doesn't harm the environment.

The hot water produced by the micro turbines is stored in huge holding tanks and circulated throughout the greenhouses during cooler nights to maintain the optimum temperature. I put it to Caroline that back in 2000, before the recent explosion of media interest in the environment, some people must have seen their plans as a little eccentric. 'I think some people did think what we were doing was rather strange but even so we still managed to get a small grant from the Carbon Trust, a government funded body, which helps businesses reduce carbon emissions.'

The couple grow a classic round variety of tomato called encore. Growing the fruit under glass ensures a long season, running from February to December, when they start planting four week old plants once again for the following year's crop.

Passionate about the quality of English tomatoes John and Caroline became involved at the conception of the Tomato Growers Association. 'The association celebrates its 10th anniversary this year and has been instrumental in raising the profile of the English tomato,' Caroline tells me.

More recently in another quirk of fate rising gas prices prompted the adoption of more forward thinking technology in the form of an anaerobic digester. Its monstrous name is matched by monstrous dimensions. 'The digester consists of six underground cells or caves, each capable of holding 400 tons of vegetable matter.' The couple's own green waste from the nurseries constitutes only a small part of the input, with the remainder supplied by the operators of trade fruit and vegetable markets such as Spitalfields and Western International Market in London. Normally they would have to pay landfill costs to dispose of their leftover produce so they are queuing up to use John and Caroline's cheaper option. Under normal conditions the decomposing fruit and vegetables in landfill sites produce methane, which escapes into the atmosphere as a damaging greenhouse gas.

Once filled the digesters are activated with bacteria this prompts the decomposition process, which creates usable amounts of methane. In a remarkable turnaround the gas is stored and eventually compressed and finally fed back, to fuel the micro turbines, completing the environmentally friendly cycle.

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