Fungus treatment help

[Dimovi]

I reported this Christmas palm about a month ago, but I am affraid I added too much fertilizer. It looks badly infected with fungus and I need help with treatment. I added some lawn fungicide in the soil. Any idea what the best way to treat this is? Can it be saved?

[Tracy]

4 hours ago, Dimovi said:

I reported this Christmas palm about a month ago, but I am affraid I added too much fertilizer. It looks badly infected with fungus and I need help with treatment. I added some lawn fungicide in the soil. Any idea what the best way to treat this is? Can it be saved?

The damage on the leaves looks more like cold damage to me.  Others have recommended to me to use antifungal solutions in the crown when there is a true fungal infection or topically where the problem exists.  I have used liquid copper successfully but there are other products.  Liquid copper can cause leaf spotting if you apply directly to the leaves, so some other fungicides might be a better option. 

Is this an outdoor potted plant in Austin?  What sort of lows have you exposed it to?

[Matt in OC]

I concur with Tracy on the cold damage.

[Dimovi]

On 2/15/2019 at 1:33 PM, Tracy said:

The damage on the leaves looks more like cold damage to me.  Others have recommended to me to use antifungal solutions in the crown when there is a true fungal infection or topically where the problem exists.  I have used liquid copper successfully but there are other products.  Liquid copper can cause leaf spotting if you apply directly to the leaves, so some other fungicides might be a better option. 

Is this an outdoor potted plant in Austin?  What sort of lows have you exposed it to?

They are potted outside. This year we have had very mild freezes in the low 30s, but I take the Christmas palms indoors when it freezes. It is possible that the temperatures got very close to freezing while they were outside or even 32 briefly. I thought it might be fungus because one of my Pindos that I repotted experienced similar damage, while the Pindos I that I did not repot seem fine. All plants are about 1 year old. If this is frost damage, is there anything I can do to help with recovery?

[Merlyn]

I have an 8' tall Adonidia triple on the NW corner of my house, it got severe burn on the older leaves at about 33-34F.  Newer leaves were only slightly damaged.  Adonidia are not frost hardy at all, and tend to totally defoliate around 27-29F.  I wouldn't rule out cold damage.

For fungal infections I treat with a soil drench of Banrot.  It's expensive stuff, but I bought a 2lb bag and it ends up being cheap "per dose" for occasional needs.  I'm not sure if the damage in the picture is a fungal infection, cold, water stress, etc.