I play music for my plants too. Aside from just enjoying playing my guitar for the best audience in the world I truly believe it helps them.
I have read numerous studies that say the vibrations and frequencies help cell growth in cannabis and the best music to use is music with stringed instruments. Classical being the most effective, celtic folk or other stringed folk music being second, and symphonic heavy metal being the third most beneficial. Sorry for those that like hip/hop and r&b but your plants don’t like it.
Another common theme in these studies was how it’s best to do it in the morning as they wake up when the sun is rising. For indoor growers this is when the lights turn on. They speculate that it mimics the harmonious sound of birds and animals waking in the morning and that it makes them wake up happy and full of energy.
I’ve also heard of growers having great success using nature sounds for a few minutes every morning.
Also, please always be nice to your plants. Mean words and yelling can actually stress them out. They don’t like the negative vibes.