This tutorial is to help you learn how to change the color of many flowers all at one time. This technique could also be used for many other things. Ok, once you have your photo open in photoshop:
1. Go to the Select Menu and choose Color Range, (Select>Color Range).
2. Click on the Add to Sample Eyedropper.
3. (With the Add to Sample Eyedropper) click on one of the yellow flowers. Make sure you click on all the different shades of yellow on the flower.
4. In the preview box, when it looks like you have all the yellow flowers selected press OK.
5. (With the flowers selected) Adjust the Hue/Saturation. (Image>Adjustments>Hue/Saturation).
6. For this photo I chose to change the color to red by adjusting to Hue to about -45.