Scrub the outside of a bright, thick-skinned orange with a plastic scrub brush. Rinse well. Navel oranges have thick skins and are a good choice for drying.
Hold the orange so the brown spot where the stem was located is on the side, not the top. Cut the orange into 1/4-inch slices. Throw out the end pieces.
Poke a hole with a thick needle in the center of the orange slices where you plan to attach the orange to the floral sticks. This step is optional and varies depending on your project.
Soak the orange slices in ascorbic acid for 10 minutes to prevent them from losing their color and developing a bacterial contamination during the drying process. Drain the slices well in a colander after soaking.
Arrange the slices in a single layer on a cookie sheet or drying tray. They should not be touching. Set the tray or sheet in an oven or dehydrator. Set the temperature to 140 F and dry about six to 12 hours. About three to four hours into the process, turn the slices over for even drying.