Brown spots on cymbidium

[Noe]

I need help from anyone who have more experience. My cymbidiums have black spots on the leaves and wet brown underneath. I think they are brown rot. The only fungicide I could find was Daconil. Can I use it? Should I cut off the infected leaves and saturate the healthy ones with it? Some fungicide mentioned was Physan and Captan but they are not available locally. where can I find them?

Another problem I got is the yellowing of the stem of one cymbidium. Is this normal?

[BikerDoc5968]

Some questions....location of plants-bright sun all day, your location-state, temps, watering, feeding. Like with any orchid, cymbidium PB will die back so some of the yellowing could be normal. The brown areas look more like sunburn but ????? As for the Physan 20/RD-20, just google them and you'll find lots of places to purchase either (they are the same thing, just different manufacturers). However, they are NOT the same as Captan!

[orchids3]

Noe,
Do you have your pots on the ground and up on benches. Also need the info BikerDock asked.

[wetfeet101b]

Pending the additional info that BikerDoc asked, I would take a guess based on the two pictures.

Picture 1:
The black spots are probably fertilizer burn.
What is your feeding/watering routine for this plant?

Picture 2:
The brown edges on the base of the leaves are normal. The older pseudobulbs will drop their leaves after a couple of seasons (sooner depending on genetics).
The darker brown spots look like physical bruises - again not a concern when in small, isolated spots.

The potting mix looks way too dry though. Cymbidiums like to keep their roots moist (but not underwater) during the warm weather, and a little drier in winter to prevent freezing the roots.

[Noe]

Thanks guys: Answer to BikerDoc's questions:
1. Outside, shaded, some sunlight in the morning and late afternoon.
2. Temp: Am in San Francisco Bay Area--60-90 degreesF.
3. Waters 2x a week, lukewarm water. Fertilizes every 2 weeks.
4. Right now on concrete floor. Noticed some ants. Building benches for them.
5. Trying H2O2 on brown spots, don't know if good idea.

Would appreciate any advice.

[BikerDoc5968]

I have similar problems with my cymbidiums....the only place I can get enough light for them is on my drivway and my discoloration may be secondary to sunburn or too much food or both....

[orchids3]

Noe's advise is good. Keep the plants watered better and cymbidiums should be on benches with all parts of the plant at least 18 inches off the ground. Cymbidiums are subject to soil born diseases even from rain water splash. When I did grow in California (I am in Florida now)
I had a lot of leaf tip die back - its from the minerals in the water. The least expensive way to prevent it is to flush out pots with water every 3rd or 4th watering. That perevents mineral buildup in the pots and some of the tip die back. Letting the plants get dry only worsens the condition - so again - keep the media moist not soggy.

[wetfeet101b]

BikerDoc,
Your cymbidium is showing symptoms of both sunburn and mineral burn.
The black leaf tips indicate mineral/fertilizer burn. Frequent flushing will minimize this problem.

The circular brown spots along the leaves are sunburn marks, compounded by mineral burn on the outer edges of the sunburn.