Fancy growing some giant sized vegetables in your garden? Grab a bag of ZooDoo and your plants may just get a mammoth sized growth spurt, as the compost is made from the poo of elephants in Auckland Zoo.

The New Zealand zoo's two elephants get through around 100kg of bamboo, sugar cane, banana palm and willow plants each day, but a new environmental emphasis launched by the zoo means nothing goes to waste, as the vast amounts of elephant, and other zoo animal dung, is transformed into a fertilizer for the zoo's gardens, while any food waste is used to fuel their worm farm.

It is green schemes such as these that has helped the Auckland Zoo achieve the highest international environmental management rating this month, the catchily titled ISO 14001 - the global standard of measuring and monitoring environmental performance. The accreditation comes two years ahead of the zoo's 2009 target to achieve the standard, and follows hot on the heels of achieving another 2009 environmental goal by 2007 – that of recycling 85 per cent of all zoo waste.

As well as creating ZooDoo, the Auckland zoo also opened a state-of-the-art veterinary center in late 2007, which is setting the standard for zoos worldwide. From its large public viewing gallery, visitors can watch staff at work in the treatment room and operating theatre and as well as contributing to valuable conservation research the veterinary centre is also eco-friendly. The building features grey water collection to supply water for all cleaning, as well as supplying water to the zoo's Exotic Birds section; recycled building materials and solar hot water heating and features landscaping created entirely from plants with medicinal properties.

The Auckland Zoo's environmental policy is one that could be easily adopted by other zoos worldwide, for as the zoo director, Jonathan Wilcken, states, "reducing our environmental footprint is the most important conservation action we can all take for the planet."