Where I live we have 3 species of hummingbirds: Black-chinned, Calliope, and Rufous. We also have A LOT of them! One cold rainy morning last week I happened to be out on the sunporch feeding the dogs and noticed just how many there were visiting our main feeder.
The feeder has flowers for 6 birds. And there were up to 10 hummingbirds drinking or waiting their turn to drink! I even saw a couple birds sharing a flower.
It had been colder than normal the night before, and it was really wet out. Some of the birds looked just miserable, like this one sitting on the empty bird seed feeder that I still haven't taken down from the winter.
4 parts warm tap water
1 part sugar
I typically use a 4 cup measuring glass and put in 4 cups of warm water and then add a cup of sugar.
In the fall, when the birds are preparing to migrate south, I often up the sugar content to more like 2 parts sugar for every 4 parts water (so 4 cups warm water & 2 cups sugar). This helps them get extra energy stores for their long migration.