A zoo in the United Kingdom has come up with a novel approach to locally sourcing some of its food for animals and dealing with the challenge of limited space: vertical farming.

The Paignton Zoo in South Devon, working with Valcent Products (Eu) Limited and its VertiCrop farming system, has just finished planting its first crop of lettuce.

According to Valcent, the Paignton VertiCrop project is capable of producing 11,000 heads of lettuce every four weeks or so. The idea is to plant the greens so that the zoo can harvest fresh vegetables daily for the animals that eat them.

Eventually the farm will have vertical plots of red chard, mizuna, mixed leaves, various herbs, edible flowers, wheat grass and barley.

The grow area at the zoo sits in a specially constructed polytunnel and has computerized controls that automate water supply, irrigation and the environment around the VertiCrops. There's also a conveyor belt for loading and unloading plant trays.

The system is intended to be low maintenance. Three zoo-workers were trained to look after the farm and are expected to do so on a rotating basis. According to Valcent, the site can be maintained by a single team member spending only two hours each day in the vertical fields.

The farming system is expected to help the zoo cut its feed bill by about