If you’ve ever wondered why cities keep getting hotter, or what each of us can do to help make our urban spaces a little greener, this episode is for you. I talk with Joshua Harrison, co-founder of Leaf Island, who shares some practical and creative ways cities—and individuals—can cool down our environments, using plants, water, and even recycled Styrofoam. You’ll find out how city design can actually repair our “broken metabolism” and why city rooftops and walls may hold the key to healthier urban living.

Listen in if you want to get inspired by the simple science behind planting (and why it’s not just about trees). We dig into how waste like Styrofoam can become soil for city gardens, and chat about why making things modular makes green roofs easier for everyday people. Plus, you’ll learn:

• How the urban heat island effect impacts city life, and what can actually be done about it

• A new way to think about city “waste”—and how it can fuel regeneration

• Where to start if you want to make your own home or neighborhood more plant-friendly

Connect With Joshua Harrison
Website: https://leafisland.org

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Chapters

00:00 Intro & World Cities Day
00:37 Meet Joshua Harrison
01:03 Turning Waste Into City Soil
01:22 Why Are Cities Getting Hotter?
03:33 Cities’ Broken Metabolism Explained
08:39 Why Isn’t Every City Full of Trees?
10:17 Why Plants Matter Most
12:08 What Is Gaia Soil?
14:00 How Styrofoam Becomes Green Roof Soil
18:54 The Modular Green Roof Solution
21:44 City Innovation Around the World
22:13 Measurable Results From Green Infrastructure
25:28 How You Can Make City Greener
30:31 Where to Learn More
31:37 Wisdom To End The Episode
32:03 Outro