Please help me diagnose/ treat my Camelia tree. It is a standard camelia we have had for around 4 years now. In the last couple of years the leaves have yellowed and are brown and crispy in places. The tree is placed in a spot that gets some direct sun as well as shade through the day. It has never flowered in the time we have had it. I've tried increasing watering, reducing watering and giving it a feed but it has made little difference. Do these leaves need to be pruned off? Thank you for any words of wisdom.