Why are my azalea plant flowers falling off as soon as open. We have checked no sign of any bugs or scale on branches.

Question

They are in plant container and have been established for a number of years.

Answer 1

This could be a fertilization issue if you do not fertilize regularly. Also, have they outgrown the container? Are they rootbound? Has the soil ever been replaced or added to? Also check the petals for spots, which can indicate a fungal disease, petal blight.

This article will help: https://www.gardeningknowhow.com/ornamental/shrubs/azalea/common-azalea-problems.htm