Spots normal or not?

[Ridley Ann]

I have some spots on my oncidium that either I just haven’t noticed or have just started showing up. Is this something I need to be concerned about? Should I spray with hydrogen Peroxide just in case?

[rbarata]

I wouldn't worry about it...oncidiums are prone to that kind of spots.
Be careful where you use H2O2...never on the roots and on the rest of the plant it must be diluted in water.

[SouthPark]

Originally Posted by Ridley Ann

I have some spots on my oncidium that either I just haven’t noticed or have just started showing up. Is this something I need to be concerned about? Should I spray with hydrogen Peroxide just in case?

If the spots are due to sucking insects, then probably better off spraying the leaves with a soap solution for plants, like natra soap or something.

Give the plant leaves and roots good air circulation - all of the time, and if you can ----- just water the growing media and roots only.

Check to see if there are signs of 'scale insect' on the leaves. If there are signs of that, then may need to use a cloth or something with soap solution to remove them. Followed by a nice spray of soap solution on the leaves. And if any water happens to get into the crown area, then might have to tip the plant upside down to get rid of any water buildup.

[rbarata]

Do you grow it outdoors?

[neophyte]

is it true that brown spots surrounded by a ring of yellow are usually a sign of fungal/bacterial infection? and that scale (or is it mites) usually causes leaves to develop a silvery complexion? that's what i've read somewhere. i'd say it's a fungal infection - as rbarata said, certain oncidiums are prone to develop spotting (eg. Oncidium Sharry Baby).i think you should just try to avoid getting water splashed on the leaves during watering and provide adequate air circulation (as per southpark's advice).

[Ray]

About the only way to avoid such spotting is to have high humidity, good air movement, and irrigate with pure water containing a tiny amount of fertilizer, while keeping all insects away. A tough combination to achieve for the home grower.

A spot surrounded by a yellow ring may be an indication of an inset bite, with juices sucked out of the immediate area, but could also be a fungal infection if a water droplet stood on the leaf and became an incubator.

A silvery sheen to leaves is often an indication of mites, which love the thin leaves of oncids, and thrive when RH is low.

[Ridley Ann]

Wow thanks everyone!

I do keep my orchids outside, but in a screened in porch. I live in central Florida so the humidity is always there so I don’t have to worry about that. The last week we’ve had A LOT of rain so I’m not sure if that had something to do with it. (I just noticed these spots but that doesn’t mean that they haven’t been there for a while.) This plant is next to my other Oncidium and that one doesn’t have any spots that I can see.

[WaterWitchin]

Originally Posted by Ridley Ann

Wow thanks everyone!

I do keep my orchids outside, but in a screened in porch. I live in central Florida so the humidity is always there so I don’t have to worry about that. The last week we’ve had A LOT of rain so I’m not sure if that had something to do with it. (I just noticed these spots but that doesn’t mean that they haven’t been there for a while.) This plant is next to my other Oncidium and that one doesn’t have any spots that I can see.

Yep, plenty of humidity there. And now a LOT of rain. So do you have a fan blowing on them? Mine are all outside in Kansas heat and high humidity, and record rains this year in my neck of the woods. I usually have a fan running on them from about 5:00 a.m. to 9:00 p.m. This year I've had to just leave the fan on 24/7 and I'm still getting some spotting. I figure what I'm using in extra electricity is offset by not having to water all the rest of the gardens this year.

[Ridley Ann]

So my spots are turning into dying tips We did just get a week of non stop rain but I’m not sure if it’s the high humidity or not because my other Oncidium isn’t spotting at all. Do you think I should cut back the brown tips?

Also it’s got two new growths popping out so I know it’s still growing. I’m just not sure what to do.

[SouthPark]

If the dying tips aren't due to over-fertilisation, and assuming the issue is fungal ---- then another remedy we try over here in Australia is "Yates Anti Rot Phosacid Systemic Fungicide". Maybe there are equivalents over there where you are.