Alicante, like many fast-growing cities, has a problem: a crippling lack of parks and communal areas. The thriving Mediterranean tourism hub offers its inhabitants a measly 5m sq of public space per person - half the national average. But now local architecture practice Barbarela Studio has come up with an innovative solution that could provide a blueprint for future expansion and a means of combating urban pollution: the Jardín Vertical or Vertical Garden.

The 22m-high fluorescent yellow and green tower sits at the entrance of Las Cigarreras Cultural Centre - a newly renovated mixed-use facility in the centre of Alicante, on the site of the city's former state cigarette factory. The Vertical Garden is home to more than three hundred local and Mediterranean varieties of plant, selected for their resistance to the extreme climate of Alicante and their low water consumption, and producing oxygen to counteract urban pollution.

Ironically, this was not the original brief. The seven-storey metal structure was built to house the new Cultural Centre's service facilities. However, during the renovation, the decision was taken to shift these to another part of the centre, leaving behind a building that no one knew quite what to do with.

Instead of dismantling it, Barbarela Studio proposed re-purposing the tower, transforming it into a public educational centre exhibiting regional plant varieties on its 3m-high walkways - a kind of museum of local flora. This project was green-lit by the City of Alicante, but in a further twist the Vertical Garden is now employed instead as a horticultural laboratory and nursery supplying landscaping projects elsewhere in the city.

Although currently not open to the public, flexibility is the key to the Vertical Garden's success, and Barbarela Studio hopes eventually it will be used as an urban park in the sky, helping to regenerate this choked up part of central Alicante and providing much-needed public space.