I can’t speak for your hummers, but our sunbirds get pollen, with small insects and spiders, with their flower nectar. A well balanced mixed diet. Sugar water only is not healthy?
Tiny insects for protein https://www.allaboutbirds.org/news/feeding-hummingbirds/
More info in the comments here https://www.allaboutbirds.org/news/should-i-use-red-food-coloring-in-hummingbird-food/