Oncidium with brown spots on leaves
 

Hello,

I have an oncidium that has quite suddenly developed two oval brown spots on a leaf. Around the spots appears to be a watery, dark green, translucent area as if the cells in that area are affected.

This plant has had a history of leaf spots, so I have been carefully watching the new, clean growth for months. These spots were not there two days ago, when I applied a preventative spray of Physan 20.

I have sprayed again with Physan 20 today, but the watery-looking area around the two spots has slightly expanded since then.

Any ideas? It seems as though the Physan is inadequate - maybe I need to get a systemic?

http://home.earthlink.net/~bmjayne_2006/Backlit.jpg

Thanks!

Oncidium are well known for having spots on leaves. It could be water splash.

where in the greenhouse should oncidiums be placed?? i can't seem to avoid watering only what's to be watered!!:dunno:

Update:

As of last night the watery splotch around the two spots had spread a little. However, much to my surprise, this watery margin completely cleared up overnight! I am crediting the Physan for this. I am now left with two oval brown spots that don't seem to be harming anything at the moment.

So, it seems my problem is solved, for now.