In November of last year, I purchased this Chinese tea bonsai (aged 46 years, in training 5) from the King of Prussia branch of Bonsai Art Gallery based in Hempstead, NY. I have been hoping that it would be with me a long time, but the picture below shows why I have been worried about it. It has been gradually losing leaves, one branch at a time, I cannot see any signs of insect or mold infestation, I have moved the bonsai to various locations to give it more or less light, I have varied the amount of water given to it, but have settled on submerging the soil in water once a week and surface watering once a week. I have sprayed it with water twice a week to no effect. For weeks, it has been getting direct window sunshine more than six hours a day, and the average temperature of the room where the bonsai is displayed is about 60Ã‚Â°. Still, still the leaves are turning yellow, then drying out and falling off.
What should I do, please, to stop this loss of leaves AND what conditions are best suited to ensure its long term health and beauty?