Why are the leaves of my dwarf tibouchina and an old camellia sasanqua yellowing?
Both my dwarf tibouchina and an old camellia sasanqua are looking sick. The former has yellowing leaves that have a spot, like rust, on them. The leaves seem to be dying and dropping. Should I feed and spray it and with what? The camellia also has yellow leaves and on some of them, a dry scaley-like covering. It is always fed after flowering with the correct food, so what is wrong wit it? It's about 30 years old.Sue
I am sorry to hear that your tibouchina and camellia are looking so poorly. I am sure with a little TLC you will soon have them looking healthy again. It is not unusual for a tibouchina to have yellowing leaves at this time of the year, particularly if it has been wet and cold. This plant needs a well drained, warm spot in your garden for it to thrive. It would be wise to remove those leaves which are showing signs of disease. If it is rust (yellow/orange spores on the underside of the leaves) you can apply a product called Fungus Gun. This product is a systemic fungicide which will control fungus such as rust. To give the plant a boost and to help it to recover, apply a product called Yates Dynamic Lifter Soil Improver & Plant Fertiliser. You will find these products at your local hardware store or nursery. From what you have said about your camellia, it sounds like it has camellia rust mite damage. This damage is cause by a tiny insect that is not visible to the naked eye. It causes the leaf to take on a bronze colour and dusty appearance. This damage is likely to have been done several months back. This coming spring/summer, you can protect the new growth that this insect attacks by spraying with either PestOil or Yates Nature's Way Vegie & Herb Spray Concentrate. At this stage, you can also apply the Uplift to your camellia and when spring arrives, fertilise with a product called Dynamic Lifter Plus Flower Food, or Acticote Fruit, Citrus, Trees & Shrubs. I am sure with the care you are going to give to your plants, they will soon recover and reward you will some beautiful flowers next year.
Answered: 19 Jul, 2012