I have a lovely Camellia, which I think may be a semi-double, although the stamens are not conspicuous. It is growing in a large pot of ericaceous compost and has been fed regularly. It has loads of flowers and buds. This is the first season since I bought it. The leaves - and flowers - look healthy (to my untrained eye) but the flowers are dropping almost as soon as they open. What is interesting/worrying is that when I pick up the fallen flowers, there is a noticeable hole where the stem should be?! Can anyone help?