When I was at university, I bought a tape for a botanist friend of the sounds of plants. Not the sounds of wind blowing gently through leaves but the sounds a plant makes as it lives and grows. It was rather strange with small squeaks and pops and the flowing sounds of water and sugar solutions making their way around the plant. I've no idea if it was real or not, but it was certainly interesting.
Rhubarb in the forcing sheds of the 'rhubarb triangle' makes a sound as it grows.
SomeBeans has memories as a child of hearing the popping of broom. This video illustrates it, sounding as though someone is holding a bowl of rice crispies next to the microphone.
But my favourite sound needs a bit of intervention. I'm ashamed to admit that I'm a Fuchsia popper. I love popping the buds. My father used to grow a lot of fuchsias, so I had plenty to pop. It becomes a bit obsessive - you have to carry on popping the buds until you get the perfect 'pop', then you can stop. For a while. It appears that I'm not the only one. It's probably a good thing that I don't have any suitable fuchsias in the garden.