Need a photo really, but a few questions to get more information - first, check the underside of the leaves,make sure there's no white deposits, eggs or aphids beneath, and second, you don't say where you are, so I have to ask, did you suffer the hot weather and drought, and did you water the camellia? Third, is it in a pot or the ground, and fourth, how long have you had the plant?

Thanks for your comments Bamboo. Plant is in the ground in Gloucestershire . Transplanted from pot 2 years ago. Did water during very hot weather, with tap water. Had loads of flowers in spring. Have been feeding with Ericacious Miracle grow. Will check under leaves as you suggest in first instance.

Be interested to know if there's anything under the leaves - otherwise, stop feeding now - its too late in the year.