Adding sugar to water lowers the freezing point a little, so I wouldn't worry about the nectar freezing unless it gets very cold. However, if you have hummers already, that means they would be drinking ice cold nectar early tomorrow, just when they need to be raising their body temps. Early last April, after 3 hummers had arrived here, we had a cold snap which had 2 nights with lows in the lower 20's, and 1 night with a low of 19. I got up at first light each morning and put out fresh, warm nectar. I don't know if it helped or not, but common sense tells me it would.

I know some people have had a light shining on them to keep the temps up. Christy :)

Thanks for the good ideas! I can leave my porch light on, but don't know how much warmth that would provide. I think I'll make up a batch of nectar tonight and replace the other first thing in the morning.

Susan

I think that if you have hummers around, the sugar water would NOT freeze. Put another way, if the sugar-water freezes, your hummers aren't going to survive the cold temperature anyway.

Regarding lights for heating... Incandescent lights get hot, but not that hot. Unless they are only a few inches away, it would have no effect. And any breeze would eliminate that entirely.

There is a physics rule about light diminishing by the square of the distance. Don't worry about the math, just know that means it fades VERY fast! :)

So, unless the outside temp is going down to about 20-25 degrees, don't worry about the feeder freezing. And don't try to heat the feeder with a light bulb. Just bring the feeder inside for the night.

And rest assured that if you have to bring the feeder inside for the night, there are no hummers around...

I have left a glass feeder out all winter long before and as far as I know it never froze up. But since you have hummers there now , I would also find a way to have fresh nectar for them early in the morning.