Get out before sunrise. Morning mist and warm sunlight will add nice color to your picture as well as shadows for contrast.
Change you perspective. Look at your subject from different angles. Get low when shooting flowers and avoid taking pictures at chest level.
Avoid taking pictures midday. During the middle of the day, when light isn't good, leave your camera in your backpack and wait again for late afternoon as the sun settles at the horizon.
The Arizona cactus picture was taken at 8AM at the beginning of April. Note the warm colors throughout the image taken at a low angle. It is a little bit busy but I was afraid to style it and remove unwanted twigs, not to get stung.