Why is grass greener underneath a trampoline?

If you’ve ever owned a backyard trampoline –or jumped on someone else’s– you might have noticed that the grass underneath it is longer and lusher than the grass in the rest of the yard. It’s not just that grass isn’t getting mowed… in fact, when it does get mowed, you can see the weird effect even better! Instead there's something else –something shadier– going on here. Plants need sun; it’s their source of energy. But too much sun can dry out the soil, overheat a plant, and overload its photosynthetic machinery, all of which can stunt its growth. Reducing the amount of sun that reaches a plant –by, say, covering it up with a trampoline that lets through only some of the sunlight– helps moisture stay in the soil, keeps temps way cooler, and stabilizes light levels for peak photosynthesis. The result, in many cases? Bigger, happier plants.