Hummingbird population information Your hummingbird feeders need to be cleaned, and the humming bird nectar needs to be changed every 3-4 days. If black spots are visible inside your hummingbird feeder, it can be a sign of mold and you will need to scrub it out with a stiff thistle brush. If you can’t reach the spots with a brush, you can mix some sand and water together and shake the feeder vigorously to remove the mold. Never use harsh detergent to clean your hummingbird feeder. Rinse the feeder out with hot water each time you change your nectar. If you do this on a regular basis you should not have a problem with mold growing inside of the feeder. Pesty ants can be a problem at a hummingbird feeder. The best way to prevent ants at your feeder is to use an “ant guard”. An ant guard is a barrier between the ants and the nectar, making them ant proof. These guards are built into many feeders but are also available as an add on accessory for existing feeders. There are certain ways to attract hummingbirds to your feeder. Red! Red! Red! All hummingbirds are attracted to the color red. Most feeders that are purchased these days have red on them somewhere, but if you are in doubt that there is enough red, try tying a red ribbon on the feeder itself. Another way to attract attention to your feeder is to place it among flowers that hummers like, or hang a basket of flowers nearby the feeder. You will find that feeder activity slows as more flowers bloom in your yard. Do not panic! They prefer natural nectar over what we give them in our feeders, so as the flower start to diminish, you will see them come back again.