It depends on temperature and amount of use. When it gets to 90 degrees and above, I change it almost daily. I have several feeders and those that are in the shade, can go every other day.

The more visitors also impacts how quickly the feeders need changed.

I use HummZinger mini feeders which have a clear reservoir. I check the feeders every couple of days. If the nectar appears at all cloudy, out it goes.

I wash my feeders in plain old dishwater with a 10% chlorox rinse. I've also run them through the dishwasher. Nothing seems to deter hungry hummers!

Rule of thumb around our house: temps in the 70s I change every 3-4 days, temps in the 80s every 2-3 days, temps in the 90s every 1-2 days. Works for me.

Good advice above. The vinegar is fine as a substitute for bleach, and probably a little safer for the hummers. Personally, I just hate the smell and feel of bleach on my hands!

I change mine every 2 days religiously.

I learn new tip from cleaning my hummers feeders. I use regular diswashing liquid in cleaning feeders. It seems vinegar is more effective and safe. I'm going to switch to vinegar from now on. Thanks.

Change mine every two days when its hot , more often if it gets cloudy quick. No less than twice a week regardless.

I clean mine every time I fill it - around twice a week.