Creamed-coffee color on pseudobulbs.

[Stringa]

Hi everyone,
We have gotten a lot of rain this summer. I have many plants hanging outside. I also have a lot of plants inside. Some of the pseudobulbs on my plants (cattleyas and oncidiums) outside are starting turn the color of coffee when creamer has been added to it. This happened to most of my plants last year and a lot of them died. I am not sure how to handle this.

I really treasure these plants that have gotten attacked by this. I would be vedry greatful for an opinion on how to deal this problem. Last year I cut the brown stuff off, sprayed the affected area, and the rest of the plant, with with Physan 20. This only helped a few of the plants. For the rest of them I had to call the priest after driving them seven hours to have an orchid doctor in Tampa examen them.

I am not sure whether to go ahead and discard these plants or try to save them. Luckily there are only a few that have gotten the disease this year. This is my second year of growing orchids. So I learned a lot about how to kill them last year when most of them died.
There is no orchid society less than two hours away from where I live, so I have no experts to ask. I e-mail some reputable growers hours away from here in a panic about bumps on the leaves, and they just don't understand how well I can kill a plant due to lack of knowledge. Ha! As terrible as it is to see the plants go, it is still kind of fun to learn about the diseases that affected them.

David.

[Call_Me_Bob]

i cant help you, im sorry

but i wanted to welcome you to the forum. i understand from your profile that you aren "brand new" but i didnt get a chance to great you. so here it is,

also, i wanted to give you a bump, so here that is

[RobS]

It does sound like some kind of soft rot. Removing the infected part whith a desinfected knive while cutting trough the healthy tissue (some say 1 cm deep into the healty part.). After that treating with an anti fungal product is probably the best treatment.

More interesting would be how to prevent the problem comming back. Many orchids don't like to much humidity / water. This typically comes down to letting them dry between irrigations. Drying means that the roots should turn white again before watering again. I can imagine them being outside in the rainy season with fairly high humidity that they stay wet to long.

[Royal]

I fight this problem too, it's one of the downfalls of outdoor growing. I either have to water almost every day when it doesn't rain, but when it does rain it seems to never stop and causes issues.

The ideal situation would be to cover the plants so you can control moisture. This is tricky to do and still get adequate light. An alternative is to use a systemic fungicide like Captan. Physan is good as a preventative measure but it's not heavy duty enough for these dire situations.

Once a plant is affected, it is tough to "cure." The best option is to remove the affected tissue, sterilizing the blade between cuts. You can dust the cuts with cinnamon or seal it with a slurry of cinnamon and elmer's glue. Sometimes removing bad spots can mean unpotting the whole plant and cutting away the bad parts at the rhizome.