Hi Liz,

You don't need to add food colouring, it doesn't do anything except cost more and it could actually be harming the hummingbirds.

Just heat in a sauce pan 2 cups of water to a low boil 1-2 minutes. Then take off of heat and stir in 1/2 cup of White Granulated Pure Cane Sugar (4:1 water to sugar). Let it cool completely and put some in your feeders and the rest can be stored in the refrigerator for up to 10 days. Change the nectar in the feeders every 3-4 days so it doesn't go bad. And to wash the feeders sprits completely with white vinegar from a spray bottle then rise thoroughly with tap water.

The red dye has never been proven safe for hummingbirds to ingest but it has in fact been proven harmful to humans.

-Joe

Here is a link that might be useful: nectar mix

Liz,
Joe is right, NO RED FOOD COLORING!! I used to boil, don't anymore. Can't tell any difference. I nuke my 1 qt measuring cup of water for about a minute just to make the sugar dissolve faster. If you are in MS, your hummers are probably Ruby-throats.