The mayor of Paris, Anne Hidalgo, unveiled plans this month to create new parks and gardens on some of the French capital’s busiest roads. It includes the Champs-Élysées, the elegant avenue famous for shops and restaurants but also for 8 lanes of busy traffic.
The “re-greening” of Paris has been going on for a couple of years now. The aim is to plant 170,000 trees by 2026. And some spectacular gardens in the city centre should be ready in just 3 years, when Paris will host the 2024 Olympic Games.
The heat is on
So why the hurry? Well, the world is getting warmer. The ways we all eat, make things and get about are all adding carbon dioxide (CO2) and other greenhouse gases to the air. In cities, even in northern Europe, hotter summers are becoming uncomfortable and unhealthy.
One way to cool down the planet is to stop driving cars, lorries and buses that give off CO2 – by using electric motors or, better still, walking and cycling. In cities, that also means cleaner air to breathe. But another great way to reduce CO2 is to plant trees and bushes.
Plants love CO2! They soak it up and give us back oxygen to breathe. By turning parts of big roads into gardens, Paris is hitting CO2 with a double-whammy – fewer cars AND more plants! Some people call parks the “green lungs” of our cities.
Problem, solution, problem…
But hang on. There’s one problem… Forests normally take many years to grow. And trees and plants don’t much like cities, where people have been laying concrete, running factories and generally making the land dirty.
That’s where we get to meet Mr. Miyawaki. He turns 93 this week, he comes from Japan and he’s a botanist – an expert in plants. For many years, he studied the secret life of trees.
He invented the Miyawaki method for growing healthy forests, up to 10 times faster than normal, especially in cities. This is the method that they’re using to make Paris greener.
Mr. Miyawaki discovered two things. First, it’s really important for trees to feel “at home”. So, plant trees that would naturally grow in the place you want them. And second, different kinds of tree can help each other.
Modern forests often just include one or two kinds of tree. But Mr. Miyawaki advises planting up to 40 different species of tree and bush, even in tiny city parks. Nature loves variety, it seems, and that helps the trees help each other to grow, quickly.
It also attracts many more kinds of bird, insect, animals and wild plants. So in just 3 years, you can have a park with tall trees – and that is so dense and varied that it soaks up much more CO2 and dirt than a traditional city garden.
Over to you, kids!
Everyone can join in! In Paris, one typical project involves planting 600 trees and bushes from 30 different species on an area just about the size of a tennis court. It’s turning a scruffy patch of tarmac next to a busy road into a little “lung” that can soak up noise and pollution.
Schoolchildren are also getting in on the act, helping to plant trees locally. Thanks to Mr. Miyawaki, they no longer have to wait till their old and grown up before they see a forest!
Have you been involved in planting trees? Or would you like to? Let us know!