Is it necessary to boil water when mixing hummingbird food?

Boiling the water and sugar together destroys much of the bacteria and fungus that could cause the mixture to spoil and grow mold. Use a mix of 1 part sugar to 4 parts water. Don't add food coloring. Keep your feeder very clean. Any signs of sooty black mold ---dump it and clean the feeder. Keep extra solution in fridge until used.