Fortunately, it can be simple to clean a bird bath without scrubbing if you follow the proper steps. This technique will take 20-30 minutes total, though for much of the time you'll be able to attend to other tasks as the bird bath cleans itself. While the basic technique is suitable for bird baths of any material, it is most effective on concrete bird baths. If your bath is unique and delicate, take precautions to protect it before trying this technique.
Materials you'll need…
Hose with pressure jet setting
Black plastic trash bag
A very dirty bird bath!
Step 1: Dump the Water
The first step in cleaning a very dirty bird bath is to get rid of the contaminated water. This water is often filled with organic material such as feces, algae and dirt, and it is safe to use to water nearby flowers or plants. Dump the water out in an area where it will be recycled to help the rest of your garden, but treat the basin of your bird bath carefully to avoid damage. If the basin of your bath does not detach, simply tip the pedestal to drain the water onto nearby plants or grass.
To safeguard your birds from this dirty water, avoid dumping the basin near bird feeders or spilled seed that ground-feeding birds may sample.
Step 2: Rinse the Basin
Using the pressure setting on your hose nozzle, rinse the bird bath for 10-15 seconds to remove any stuck on debris, feces or loose dirt. For a very dirty bird bath you will not see much change from this rinse, but removing surface material will help the bath be cleaned more thoroughly. If your bird bath has a textured basin, be sure to tilt your hose at different angles to get in every space.
If your bird bath has a delicate surface, avoid the highest pressure setting that may loosen a mosaic or chip a surface finish. Instead, use lower pressure or wipe the surface lightly with a soft sponge.