I think my valencia has rust. What would you recommend that I spray on this? It's the only tree with rust and would like to keep it that way.
TIA,
Mimi
Citrus Rust?
I wonder if it might not be sooty mold instead? I could be way off but it doesn't look the right color for rust (at least on my computer screen!), and it looks like there's some on the leaves too. If it is sooty mold, then the key is to find the insects that secreted the honeydew that the sooty mold grew on. The mold itself is unsightly but doesn't hurt your plant, but it grows on honeydew from aphids and scale, so it would be a good idea to get rid of whichever one of those is on your tree. Then you can take some soapy water and wash the mold off the leaves and fruit.
It looks like it could some rust as well. At this point you can not do anything about the rust. This summer you will need to spray the small fruits with a horticultural oil to prevent it on next years fruit.
Lime Sulfur works wonders on citrus. Two sprayings, one in winter and one before the tree flowers. It’s organic, not terribly expensive and will address most of your problems including mites.
Oldude
I use a product called Organocide which is also organic. It is sesame seed oil and fish emulsion. It is a great product. My big problem here is leaf miners. They attack all my citrus large or small. If I spray Organocide everyone one or two weeks it helps with this and most other problems as well. The trees like for the fish emulsion as well.
Dale
Use copper sulfate spray in early morning or evening for rust or other fungal diseases. That's more likely to appear on the leaves.
Your fruit looks like normal Florida fruit. Perfect ones scare me.
Hort. oil/water spray on leaves late in evening control insect pests. Ants farm aphids like people do cows; they even move them.
I hope you've picked and eaten them by now (Aug).