this isn't a proved theory but it never hurt anyone to try it. Mythbusters did an episode on it where they tested the theory, they tried different types of music and also tried talking to them like talking nice and softly to talking mean to the plants. in the end the test showed that the plants that listened to hard core rock/metal grew the best. my best bet is that whatever satisfies the gardener usually makes the plants grow because people are more comfortable when they listen to music they like and if they listen to it while gardening, their comfort and happiness usually reflects off to the plants.
flower
your flower can grow faster with flower food and by talking to your flower just saying that its pretty or read them a story
water
sun light
Over a given short time tulips will grow faster from bulb shoot to flower.
no
No plants want grow if they don't have sunlight at all.
Black dirt makes flowers grow faster because it will attract the sun, you may need lots of water.
A flower will not grow faster with salt water; in fact, salt water can be harmful to plants by interfering with their ability to absorb nutrients. It is best to water plants with regular, fresh water for healthy growth.
yes the sound waves affect them and make them grow faster
plants like country music better so YES.
dirt gravel because it has some nutrients in it and gravel does not.