I thought this might have been the one about the lush (but dangerous!) Venusian rainforest!
(In Bradbury's time, we knew Venus was covered in thick clouds, and could only speculate about what might be beneath the clouds. Clouds = rain = lush vegetation?)
Same, seeing the title and having not read Bradbury for a long time I was thinking either The Veldt or that one (The Long Rain). I did remember it on reading, though, and it's an unsettling feeling.