To identify flowers by pictures, observe the image and note details about the flower or plant, such as the pedal shape and color, the leaf shape, the plant's size and any other unique characteristics. If you take a picture of a flower to identify, make note of its location and the season. To narrow down the search results, use a plant identification resource such as an online database, or find one at your local library, bookstore, university or garden center.
For plants native to the United States, the Lady Bird Johnson Wildflower Center database is an excellent resource to identify flowers by pictures. The search tool asks for basic information, such as the state or province where the plant is found, habitat, lifespan and characteristics such as height, appearance, color and leaf arrangement. Enter this information in the search tool, and use the image results of the search to identify your picture of a flower.
Electric field guides also identify flowers by pictures. Apps exist to identify plants from a photograph. Simply take a photo with Google Goggles and submit it for analysis. Most of these apps have a list of characteristics that aids in identification, similar to print guides and online databases.