what is a recommended fungicide for citrus trees?
It would be better to match your request for a fungicide recommendation to a specific fungal disease. Those that are of the biggest concern in Texas include Sour scab, Sweet orange scab, Melanose, and Greasy Spot. At harvest time, blue mold and brown rot are often seen on fruit.Since you are asking this question in February, I would have to assume you are concerned with the first group of fungal problems I mentioned. All are afforded some control by use of neutral or fixed forms of copper--either basic copper sulfate or copper hydroxide (Kocide brand products). Pre-dormancy sprays with a copper fungicide can reduce incidence of Melanose, scab and greasy spot, but they can also increase problems with mites if over-used. Thus it would be wise to have your disease problems identified and make appropriately-timed sprays, rather than calendar-based or "scheduled" sprays.