In late June, we were fortunate enough to get the opportunity to visit Evesham Vale Growers, one of the country’s largest producers of tomatoes, as well as other crops such as spring onions and courgettes. Our horticulture consultant Richard Lewis shares his review of the fact-finding mission…
Business History And Background
Set in the ‘Heart of England’ in the Vale of Evesham, Worcestershire, Evesham Vale Growers (EVG) is a success story that has developed over nearly forty years from humble beginnings to become the largest vegetable producer in the area. Still a family-run business to its very core, EVG was formed in 1976 by two Italian brothers who had emigrated to the UK in the 1960s. The business started out by growing and selling bunched spring onions for the wholesale markets and local outlets, and within a year it was supplying supermarkets including Sainsbury’s and Morrisons.
In the late 1980s, M&S was at the forefront of significant innovation in the tomato category, introducing new varieties and concepts such as tomatoes on the vine. In a bid to catch up, Sainsbury’s sought the help of EVG, and ever since, the business has evolved to become one of the largest growers and packers of tomatoes in the UK.
In 2000, EVG purchased a 650 acre farm in Fladbury, which was added to in 2009 with an additional 65 acres at Middle Littleton. The following year, a further 670 acre farm was purchased at Throckmorton, while upon the demise of a competitor, EVG picked up a tenanted 600 acre farm as well as 200 acres of owned land in and around Charlton. Now, the business farms around 2,500 acres right across Worcestershire, as well as growing and marketing tomato production under 50 acres of glasshouse.
Like many businesses it evolved slowly, using the buildings it had until the point arrived where greater attention needed to be given to the design of the tomato packing sheds to try and increase efficiency. Greenhouses were taken down and new packing sheds were constructed with the intention of streamlining product flow. Within the newly-designed unique packing lines, fetching and carrying was reduced and in some cases eliminated to the extent that 40% of time was saved. The line operators now stayed at their stations and all the produce was delivered to them through the use of conveyor belts; even the rubbish was disposed of efficiently. The quality controllers have a responsibility to check shelf-life standards by taking two packs from each ‘run’ and monitoring quality so that any problems can be highlighted and traced not only to a specific line, but also to a particular greenhouse.
The staffing of the lines was considered in such a way that all records demanded to comply with British Retail Consortium standards could be completed efficiently on a daily basis, and their monitoring visits no longer became the headaches they once were. Other audits could be dealt with the confidence that all requisite paperwork was in place.
Evesham Vale Growers currently employs in the region of 600 staff providing steady work through the summer and winter. The majority are Eastern European coming in from Poland, Latvia, Lithuania, Bulgaria, and Romania, with a few from Slovakia. This, as can be imagined, can cause problems with the range of languages spoken. In the packhouse alone where 200 are employed, less than 3% are from the UK. Training is provided as required and promotion is considered on merit and availability of positions. The positive work conditions and atmosphere are an important factor and this leads to a retention rate in the office of 100%, on the farm of 93%, and in the packhouse of 83%. There is always an element of the ‘grass being greener’ for some, but this retention rate speaks for itself.
The tomato production at EVG’s Offenham glasshouses is home to the largest LED trial in Europe. The greenhouses use a combination of sodium and LED lights. If ambient light levels fall to less than 450 watts then the artificial lighting is used. In winter it is possible to light the whole crop.
The success of the system can be measured in terms of yield, with a staggering 25% increase in crop over last year’s figures and comparatively a 20% improvement over nurseries not using LED. The yields are dependent on the varieties grown, but the most efficient varieties can return up to 100kg/square metre. The general figure is about 65-70kg, although in some of the older houses 15kg/square metre may be the maximum. In a cycle of a January plant through to November the firm may struggle to acheive 50kg, but with a September plant and a pick starting in November it will hope for 70kg.
It is predicted that return on investment for the cost of installing the lights will be achieved within six or seven years. Due to the height of the greenhouses, it is possible to position the sodium lights well above the crop above every other row, but careful recording of yields has indicated that the rows with the sodium lights directly overhead can result in a crop increase of 10%.
The use of grafted plants has led to increased yields, but these increases are not generally seen until the March-April period. Through the winter the crop increase is not appreciable, but the crop management is hampered by the growth vigour, making the plants heavy and harder to handle, side shoot, and train. It is not unusual to see heads snapped off and replaced with side shoots. Dipping the temperature of the glasshouse early in the morning helps to form a stronger truss. This is easily undertaken in the winter by just opening the vents, although it is appreciably harder to control in the summer.
The trial work that EVG’s Stockbridge glasshouse has been carrying out with LEDs has used PAR light with a proportion of 4:1 red to blue light. It has also been working on developing LED lighting growth strategies which fool strawberry plants into thinking it is already spring.
Other elements of efficient working include the amount of downtime a greenhouse will experience. The turnaround time from stopping picking to completion of planting can be as little as eight days, which is achieved by mob-handing the work with as many staff as are available. A completion of the crop at the end of August can then result in picking re-commencing in November. This is in part achieved by the size of the plants that are replanted into the hydroponic troughs. They are grafted 60 day plants that are in first flower open and have to be held up by sleeves to stop them from flopping over. Plants are sourced from Plant Raisers Ltd in Yorkshire and in some cases grafted onto more rootstocks that impart vigour to the haulm. Plant Raisers Ltd was formed following a management buyout of the propagation business from Crystal Heart in August 2002. The business has developed such that it is now the biggest propagator of tomato, cucumber, and pepper plants in the UK and is the only one to have a quality system certified to conform to ISO 9001:2000.
Much of the EVG tomato business uses a hydroponic system for two reasons. Firstly, there is a potential risk of the glasshouses flooding which can wipe out a crop, but also because of the need for an accurate ‘fall’ in the greenhouse for the troughs, with some of the houses being up to 100 metres long this can be problematic for the materials handling of the picked fruit in the trolleys. With the troughs being off the ground the house floor can be maintained as flat and the slope governed by the adjustment of the trough stands – another benefit it that the ripe tomatoes are presented at an ergonomically friendly picking height!
Pollination And Pest Control
The crop quality is managed through the use of biological control, meaning the need to wash off pesticides is reduced. Bumblebees supplied by Syngenta are used for pollination. The management of the crop is important as tomatoes produce little nectar and bumblebees require sugar for flight energy and feeding their colony. They require pollen as a protein source for reproduction, so to this end Syngenta provides freeze-dried pollen as a supplement to maintain colony growth.
The colonies of bees are not long lasting, so are generally removed after about 10 weeks through the renewal process so that wasps do not get a chance to colonise the boxes. Deliveries of three boxes every fortnight maintain the strength of the pollinating population.
The use of biological control is important to ensure the use of pesticides is kept to a minimum. Tuta absoluta, or the South American tomato moth leaf miner, is a particularly nasty little insect that has become endemic in tomato crops across the world. The moth lays its eggs on the plant and the larvae burrow into the fruit, making it an extremely difficult pest to control. It also developed resistance to pesticides very quickly. The use of Macrolophus calioginosis or Whitefly predator bug as the biological control has gone some way to controlling the problem within the crop.
Mildew is contained through control of the environmental conditions, but the crop will need spraying occasionally to keep ‘hot spots’ under control.
During change-over, glasshouse hygiene is paid attention to by fogging with fungicide that doesn’t affect Macrolophus, while during this period the glass can be washed down with high-pressure hoses to maintain light transfer.
During crop management the side shoots and trimmings are left on the floor to shrivel up. This method has two benefits in that it saves money having to haul out and dispose of the trimmings and it allows any Macrolophus that are on the trimmings to get back to work. Any Tuta that are infesting the crop are generally on the higher leaves so are not affected by removal of the trimmings.
Generating Renewable Energy
Over the years, Evesham Vale Growers has become synonymous with excellent ‘green’ credentials, due to initiatives such as the installation of a 100 acre solar farm with substation at Throckmorton. The land under the panels is not lost as it is grazed by sheep. Despite reductions to government Feed-in Tariff subsidies, the solar farm still provides a favourable return on investment.
Through its Combined Heat and Power plant (CHP) good levels of gas and energy are also produced. The CO2 is fed into the greenhouse as enrichment and pipes under the troughs are used to maintain air movement and stop stagnant air developing.
EVG also has two anaerobic digestion units, which combined can produce up to 23.5 MW of energy. The installation of the Anaerobic Digester at Fladbury caused a few problems, however. Taking care of bacteria is not as simple as it is perhaps made out to be, and in the early days mistakes in the feeding of the AD unit caused it to be shut down for several days.
The first unit was 85% completed before problems with the contactor occurred, leading to EVG completing the construction in-house. As a result of this new-found confidence they went on to build the second unit themselves.
The digesters have several valuable by-products: gas which is mixed with propane (for identifiable smell!) and then metered as it is added to the grid, renewable electricity that is then used to power lighting and heating in the greenhouses; CO2 for enrichment; and solid digestate for spreading on the land to replace the need for fertilisers – this final benefit can cause its own particular problems though. While it is ok to spread during spring and summer, it can cause issues during the winter, as spreading on the heavy soil could – without careful control – result in run-off and river pollution during wet periods. As a result, this excess digestate is stored in tanks and slurry pits until it can be safely disposed of.
Typical values for digestate nutrients are:
Nitrogen: 2.3 - 4.2 kg/tonne
Phosphorous: 0.2 - 1.5 kg/tonne
Potassium: 1.3 - 5.2 kg/tonne.
Over-production of gas resulted in the need for membrane storage units to take care of the surplus.
The AD units are greedy set-ups and demand a ready supply of food to feed them, so EVG grows maize and beet which is used solely to feed the units, while the firm also sources poor quality grain that cannot enter the food chain. Large areas of maize are needed for an AD plant, for example, a 500KW anaerobic digester requires approximately 220ha of maize silage.
Water re-cycling has been included into the site at Fladbury, which has a gravity-fed reservoir from the greenhouse roofs. The facility has a pump unit that can move the water to the spring onion packhouse for washing.
Land that is not used for the production of digester silage produces a broad range of vegetable crops. By far the main crop is asparagus, which is one EVG is renowned for. Asparagus beds will last about 10 years before being rotated to spring onions, courgettes, or maize silage. As a long-term perennial crop, perennial weeds can become a significant problem. Efforts are made to clean the ground prior to planting and establishment, but once growing the weeds have to be controlled through the use of targeted sprays applied after a severe cut to reduce the above ground target.
Bunched spring onions are still a mainstay of the firm – these must still be lifted by hand due to the fragile nature of the plant. The crop is washed, graded, bunched, and packed in a bespoke facility that is run on similar efficient design principles to the tomato grading line.
Stick beans on low canes are another labour-intensive crop – these must be also picked by hand and continue to be picked even when the price drops, as unless they are picked they will stop cropping. The low cane crops make picking easier and more efficient.
Courgettes, while needing to be cut by hand, can utilize a harvesting rig, enabling the team to traverse the field cutting the crop. The rig then transports the crop via conveyor to the packing facility on the trailer.
To enable crop rotations to work, sometimes land is ‘borrowed’ or swopped with other growers to allow different crops to be grown, thus maintaining the heart of the soil.
EVG continues to supply most of the major supermarkets, including Sainsbury’s, Morrisons, Aldi, Asda, Iceland, The Co-operative and Waitrose. Other contracts include Nandos and Walkers, where tomatoes are used to flavour crisps, while – if available – asparagus gets sent to the Wimbledon tennis tournament.
Looking to the future, EVG has further plans to expand and at present is exploring the feasibility of increasing the greenhouse area by 12 acres and the solar panel area by another 40 acres.