How do you create green spaces in the middle of a city, where there’s no space to create large-scale parks or gardens? Paris has come up with a clever solution – they allow anyone to apply for a permit to start a garden anywhere at all. A rich assortment of small projects has sprung up, ranging from plant pots around lamp posts, to rejuvenated church squares, to walls covered with ivy. It’s a piecemeal approach to making the city greener, but it’s one that seems to be working. This week on World Hacks we visit this and two other projects that are trying to improve our experience of urban public spaces. As well as Paris’ citizen gardeners, we’ll hear from joggers in India who are ridding their streets of litter and commuters in London who are making a small but crucial change to the way they get to work. Presenter: Harriet Noble Reporter: Amelia Martyn-Hemphill Photo Credit: Getty Images