Mold forms on objects that are wet and if the surface of any given feeder is not regularly cleaned, mold spores will eventually attach themselves and inevitably, form mold. Colder climates won’t require maintenance as regularly as hotter temperatures (15 – 27°C) but, no matter the weather it will still eventually be made. 

After all, if you don’t want these hovering birds to get sick or potentially die, making sure that the sugar water is replaced regularly and the feeder stays clean has to be prioritised.

I’ll be digging into this topic in a bit more detail throughout the remainder of this article so continue reading for more info.

How Does Mold Form On Feeders?

Mold will form as a result of tiny spores developing within damp or moist environments. Feeders are prone to this due to the fact they’re outside and because of the sugar water inside them.

Therefore, mold can form on its surface as well as around areas touched by the sugar water.

In most cases mold will form within 24 – 48 hours. Within a 3 – 12 day period the mold spores will colonize. it’s only after around 18 – 21 days when you’ll be able to see the mold. This will show up as a either cloudy sugar water or you’ll notice black mold patches within the water.

To stop this from happening you should replaced the sugar as often as you can but, you can extend the time per change depending on ten weather, if you want to go with a more conservative approach.

If the weather is on the hotter side, changing every day or every other day at the latest should be fine. On the other hand if the weather is approaching winter, you wouldn’t need to change it as often. Weekly changes should be okay here although I will still advise you change it every day or every other day to limit any danger to the hummingbirds.

This longer periods between changes is theoretically fine as mold forms at its fastest between 60 – 80 degrees Fahrenheit (15 – 27 degrees Celsius) so, constant changes won’t be as necessary. This isn’t to say mold can’t grow in these conditions as there are different types but, most should be slowed down, especially if the weather is on the drier side.

What Can Be Done To Prevent Mold On Your Feeders?

The most obvious thing you can do to prevent the spread of mold is to regularly change and clean the feeders in use.

You’ll want to wash the feeder with very hot water to kill and remove the mold spores, whilst using a bottle brush or a something equivalent to rub the feeder thoroughly to remove any excess spores. Cleaning daily is ideal for hotter weather whilst cleaning it weekly or every 2 – 3 days would be fine in the colder months.

Make sure to get into the small slurp holes too. As it’s the primary way hummingbirds gain access to the sugar water, if it isn’t cleaned, fungal infections can form and result in a potentially deadly situation for these hovering avians.

Will Hummingbirds Die If They Drink Moldy Sugar Water?

Yes, unsurprisingly if a hummingbird were to drink moldy sugar water they could potentially die. If their body is unable to handle it or if a secondary party does not intervene there chances are definitely slimmer.

According to the the Wetlands & Wildlife Care Center’s Hummingbird rescue team, they tend to rehabilitate hundreds of hummingbirds, whether sick babies or adults, of which 10% or more have fungus infections from improperly maintained feeders.

Even though they do their best to try and save as many sick hummingbirds as their power allows, they’re unable to fully stop death from occurring. The disease in question would be candidiasis which isn’t very easy to treat due to a hummingbirds diet.

Summary

Ultimately, all water based feeder will get moldly if they aren’t cared for properly or due to the lack of knowledge from an individual to effectively upkeep the feeders.

What makes this even more complex is that certain parts of feeders such as the hole through which hummingbirds slurp, may not be cleaned properly resulting in fungal infections.

All in all, as long as the feeder’s contents are replaced regularly whether every day in more humid weathers or every few days in colder weather and after a good clean under hot water, most hummingbirds should be more than happy consuming the food source you’d be providing them without suffering the negative ramifications of mold.