THE REVIEWER - Andre Gardner, grounds manager, Bridgwater College, Cannington Campus
When Cannington College, formerly Somerset College of Agriculture, merged with Bridgwater Tertiary College three years ago, £5m became available for investment.
The horticulture department has benefited, with a fleet of new grounds maintenance equipment, the development of a walled garden and the construction of a glasshouse that serves as display house, production facility and teaching resource.
Although the official opening of the site is planned for spring 2009, the glasshouse building is completed and stocked, and the walled garden development only requires a few final tweaks, so the site is already open to the public on a daily basis.
But can a glasshouse that has to serve so many different purposes be a success in all aims and objectives? We take a tour of the new complex.
This building is an attractive and informative display house with temperate, tropical and arid zones. It's also a busy propagation facility. And it produces plants for the grounds and stock for retail sales. But most of all, it is a resource centre for students.
"First and foremost it is here for the students," says Gardner. There is a pause and he adds: "But we also hope to make some money from it."
The new glasshouse at the Cannington Centre of Bridgwater College is tucked away beyond the dry garden, blue garden, sub-tropical walk and herbaceous borders of the recently developed walled garden of Cannington Court; yet in many ways it is the centre of attraction. It certainly demonstrates how one glasshouse can be used for many purposes and is undoubtedly one of the best examples to be found on any college site in the country.
The walled garden at Cannington has a long history. The De Courci family, lords of nearby Stogursey (Stoke Courcy), established Cannington Priory in 1138. Following the Reformation, the priory became a mansion before reverting back to a priory in the early 19th century and occupied by Benedictine nuns expelled from France. The buildings and walled garden of Cannington Court became a seat of education in 1919, when Somerset County Council established the Farm Institute on the site. In all its history, though, it has never seen anything as grand as this new glasshouse complex.
A working garden for centuries, the site is surrounded by Grade II-listed walls and is overlooked by the priory church and other historic buildings. With the aim of making the garden an area for learning and training, and also a classic garden in south-west England - a must-visit venue on the tourist route - nearly £200,000 has been spent on developing the 1.2ha site and £500,000 to build and stock the glasshouse.
It was clear from the start that any development of the walled garden, and definitely the construction of a modern glasshouse, had to be sympathetic to the surroundings while catering for the needs of the college and its students.
The glasshouse covers 1,088sq m and was designed and built by Bridge Greenhouses. It's an 8m wide-span structure, 3m to the gutters and with hipped ends for aesthetic purposes. As the glasshouse is used by students and visiting public it was deemed necessary to design and build it to public occupation standards - BS6399. It is to the same design standard as you would expect of a retail outlet; the steel work is a lot heavier than on an ordinary glasshouse and the glazing is toughened safety glass. Foundations are also extensive; a cubic metre of concrete under every stanchion.
The building began in August of 2005 and, despite less than favourable weather during the autumn and winter, it was quickly completed and fitted with the equipment needed to provide the various display zones, propagation and production facilities.
The entrance, through Kaba double, automatic, sliding doors, is via a foyer where students can meet. There are benches and notice boards, along with planting, and in the corner stands the computer that controls the seven different control zones, each with different growing regimes within the glasshouse. Bridge supplied the Hoogendoorn computer, and Hoogendoorn looked after all the IT aspects including the provision of three days of on-site training for the staff. A service contract agreement is in place to cover any incidents that may occur.
"The service contract is really important," says Gardner. "This is a big investment and the control needs to be there. We didn't look for 'cheap' - we made sure everything was done properly."
The computer is checked daily. It receives information from the external weather station and internal monitors, and communicates with the control panel in the boiler room. It is mostly set on automatic for the functions of heating, venting and humidity control, but it can be overridden and the system run manually in the event of a fault.
Beyond the foyer is the temperate zone and immediately the success of this glasshouse becomes apparent. A large, central bed is divided into dry-warm temperate and wet-warm temperate displays. Plants in this area, including tall palms and a huge olive tree carried in by a Manitou handler, are of outstanding quality. Around the perimeter, static benches brim with lush vegetation.
From the temperate zone, sliding doors lead to the arid zone, propagation facility, growing-on room, tropical display and the production area. Heating throughout is provided by piped hot water - the pipes being positioned overhead to leave an uncluttered floor - fed from a gas-fired boiler at the rear of the complex. Crucially, thermal screens have been installed to reduce the cost of running the system. These are on a rack-and-pinion system. It cost a little more than a wire drive, but, according to Gardner, is nice and positive. Hoogendoorn motors open and shut the vents as dictated by the computer.
The propagation facility employs a MacPenny mist irrigation system and heated benches. Next door is the growing-on room. Local firm Phase installed all the electrics. "It's great having everything automated; I don't have to worry about it at all," says Gardner.
He admits there were a few teething problems with the automation, but nothing extraordinary, and the problems were rectified within days.
The arid and tropical zones, like the temperate zone, each have a central display bed and surrounding bench. The beds were dug out to a depth of 400mm and filled with special compost, formulated by Roffey. The static benches were supplied by Clovis Lande. Lighting throughout the glasshouse complex is standard fluorescent tubing. It's there for late night working and evening lectures, not for growing purposes.
While the arid zone supports a fine display of cacti and succulents, it is the tropical zone that is perhaps the jewel in the crown. It has that typical tropics-like smell and the sort of atmosphere that instantly mists the camera lens. It is here where bananas grow alongside an old apple tree draped with Spanish moss. But Gardner is modest: "It's not rocket science if you've got the right temperature, the right watering regime and the right compost," he says.
Running along the rear of the complex is the production area. This is the largest section and is the "activity" centre. It is here that students are challenged by plant identification tests and undertake project work. Here, too, are plants grown for the annual borders in the walled garden and plants for sale to the public. Although automatic irrigation was also installed to this part of the house, most of the material is watered by hand.
"Most of the time there is a lot going on in here, with student assignments and production. There's a lot to manage, and even though we tried separating the benches into different sorts of plants, we discovered the range of plants was too diverse for automatic watering. It is easier and better to water this part by hand," explains Gardner.
To the rear of the production unit is the boiler house where two small boilers - a lead boiler and a back-up supplied by Bridge Greenhouses - are located, along with the heating and climate-control panels.
It is not often that a college has the opportunity to build a new glasshouse from scratch these days. The injection of cash at Cannington has brought a marvellous opportunity to do so - and demonstrated that a glasshouse can be designed to fulfil many purposes.