When to clean Bird Boxes

[geejay]

Hello everyone

I have had a bird box outside my condo and a pair of sparrows have been occupying it for the last couple of years.

Can anyone advise me, the best time of the year to clean out the box as it looks very cramped.

Thank you 

[overherebc]

Just after any young sparrows have flown the nest each season. 

Just very hot soapy water, no chemicals.

 

[geejay]

On 2/23/2019 at 1:01 AM, overherebc said:

Just after any young sparrows have flown the nest each season. 

Just very hot soapy water, no chemicals.

 

Sorry that I have not replied earlier as I missed your reply and thank you.

Is there a particular month/s that the young sparrow leave the nest?