Today, in any mature information society, we live neither online nor offline but on life, that is, we increasingly live in that special space that is both analogue and digital, both online and offline. Imagine someone asking whether the water is fresh or salty in the estuary where the river meets the sea. That someone has not understood the special nature of the place. Our information society is that place. And our technologies are perfectly evolved to take advantage of it, (...) like mangroves growing in brackish water. In the mangrove society, machine-readable data, new forms of agency and interactions are constantly evolving. The consequences of such a radical transformation are many, but one is particularly significant and rich in consequences: how should we design the mangrove society, when it comes to the relationship between the natural and the digital? In this text, I argue that the digital blue is a great ally of the environmental green. The two work best in tandem. And if the world will enjoy a sustainable development for the environment that is also socially preferable for humanity, it will be because the green and the blue will have created a virtuous circle of nature and technology. It can be done. There is just no time to waste. (shrink)