Garden Q&A: Why are my camellia buds dropping before opening?

Whether you're a gardening beginner or expert, Irish Examiner columnist Peter Dowdall has the answer to your questions  

Camellia japonica, commonly called Japanese camellia, is an evergreen shrub that typically grows to between two and four metres with glossy, dark green leaves. File picture

Question

Why are my camellia buds dropping before they open?