FeederWatch Project Assistant says:

While it appears that the photographer added the “sweet n’ low” in jest, FeederWatch wants to be clear that hummingbird nectar recipes should only include natural sugar and water. Artificial sweeteners should never be incorporated. Here is a link to more information about feeding hummingbirds including a recipe: https://www.allaboutbirds.org/whats-the-best-recipe-for-hummingbird-nectar/. ~Chelsea Benson