A rainy day in Fallbrook brings a full house of Anna's hummingbirds to the sugar bar on our front porch. Our property has been a popular feeding station for decades. We usually feed about one gallon of sugar syrup each day, twice that amount sometimes in summer when the Black chins and Allens are migrating through. The formula is one part sugar to 4 parts water. Red coloring is not necessary or desirable. Never feed them honey in the syrup, as it can promote a harmful fungal growth on their beaks. Here's a good site on hummingbirds.