Choose the right film. Each type has its own qualities of color and light sensitivity. Avoid taking pictures in the middle of the day. Colors tend to wash out in midday, especially in summer. To see what the camera will record, squint your eyes before you shoot.
Overcast days are good for garden photography because an overcast sky evens out the contrast.
If you do shoot in bright sunlight, shade the lens to prevent streaks and hot spots on the photograph. A white umbrella may be used to shade a subject in bright light to bounce light into shadowy areas. Keep the sun at your back so that your subject is lit by the sun. Be careful not to cast your shadow onto the image. Sometimes, however, you'll want to make an exception to this rule.