black spots: disease or sunburn?
 

I noticed this spotting on my glui kai a few days ago. It had been in the shade and I moved it to an open, sunny spot. So is this sunburn, or a disease?

Thanks!

Russell

<a href=http://www.bananas.org/gallery/showphoto.php?photo=25634&ppuser=5745><img src=http://www.bananas.org/gallery/watermark.php?file=25634&size=1 border=0></a>

<a href=http://www.bananas.org/gallery/showphoto.php?photo=25635&ppuser=5745><img src=http://www.bananas.org/gallery/watermark.php?file=25635&size=1 border=0></a>

Re: black spots: disease or sunburn?
 

Let me try this again....

Re: black spots: disease or sunburn?
 

The necrosis on the 10 o'clock leaf looks like sunburn and given your description of the situation that is probably the issue.

Re: black spots: disease or sunburn?
 

Has your weather been dramatically cooler lately? Mine do that in the fall in Indiana sometimes after a cooldown in the weather.

Re: black spots: disease or sunburn?
 

Sandy, you may be on to something. That cold blast everyone was complaining about hit us on 10-16/17. The cold wind was bad and we went from upper 80's to low 40's. Besides the black spots on the glui kai, my siam ruby looks TERRIBLE. I know that it is very sensitive to cold.

When you say "mine do that in the fall..." do you mean glui kai in particular? None of my other new plants in pots look like this, they were all potted then moved out into the sun weeks later (and exposure to cold) at the same time.

Nicolas, you are correct that there is sun damage - brown patches - but I've never seen sun damage show up as black spots.

Russell

Re: black spots: disease or sunburn?
 

I learned, many years ago, what the sun can do. I had some Gros Michel that had been kept in a store. One day I took some to a flea market, that was held on the asphalt parking lot of a shopping center. There was no shade at all. Within a few hours, the leaves turned white. The white areas eventually dried up and turned brown, but I've nerver seen any black marks or specks caused by sun.

Re: black spots: disease or sunburn?
 

There are some fungal diseases that do cause black spots maybe Deightoniella torulosa which is called speckle. I'm sure that someone at Auburn Extension would be willing to help you identify it.

Re: black spots: disease or sunburn?
 

No I don't have that particular banana but I've seen it on gran nain, margarita, siam ruby, and many others here where nanas aren't too happy in the fall!

Re: black spots: disease or sunburn?
 

I moved some small basjoo out into the sun this summer, and they got identical looking small spots. They started to go away once they got back to partial shade.
I'm sure your problem is sunburn.

Re: black spots: disease or sunburn?
 

Thanks everyone.

Thirteen nights in a row of 20 degree weather "cured" the black spots!

Russell