In Chinese traditions of Feng Shui sunflower is a symbol of prosperity.  If you want prosperity and financial well-being in your house, buy a bouquet of 9 sunflowers and place it in the far right corner of the central room.  If it is not possible to purchase fresh flowers, hang a picture.  The image of sunflowers has the same energy.

In yoga, the flower symbolizes the third chakra, which is responsible for personal growth, development and intelligence.  The stronger it is, the more cheerful, optimistic and energetic a person feels.