It is in a 200mm bullet pot on our balcony , it has been here for 3 months , it has been a healthy thriving plant but the leaves havea brownish rusty appearance and are turning yellow and dropping off ,the symptoms happened almost over night , any advice on controlling this would be apprreciated , it has been in the pot for about 3 years , should i re-pot it ? I also have a 2nd Gold star propagated off the first which is approximately 18 months old with no symptoms and they live side by side , I have been using Yates Advanced Rose Gun but doesn't seem to be working pls help Tim
28 March 2019 06:16 AM
Rust can be extremely difficult to control particularly during period of warm humid weather. The spores of this fungus are spread by wind from old infected leaves to the new ones. The Yates Advanced Rose Gun contains a fungicide called Myclobutanil. It works systemically within the plant providing both protectant and curative activity to control fungal diseases such as rust. As well as using this fungicide, take care to remove any leaves that are badly infected and those that have fallen on the ground which contains spores that are likely to re-infect the plant. Provide ample amount of air circulation around the plant. I would also isolated the infected plant to ensure your other Croton doesn't become infected. You will have to continue to spray this fungicide until you get this problem under control. It may take several weeks. Because the plant is presently in a vulnerable situation, re-potting is not recommended. In saying that, do make sure you pick up any fallen leaves that may fall onto the top of the potting mix as the spores will splash back and re-infest the plant. Keep the plant as healthy as possible by applying a seaweed tonic every 2 - 4 weeks. Once the plant is free of this disease and looking healthy, you can then pot it on with some fresh potting mixl Good luck in controlling this nuisance disease.