Miltassia Charles M Fitch –*reddish spots form on top pseudobulb leaves only - what??

[astrid]

Hey everyone!

This is a Miltassia Charles M Fitch my boyfriend purchased for me from The Orchid Gallery via amazon.

A few months ago, I noticed the top leaf on one of the pseudobulbs develop a rusty reddish blotching at the leaf base. It was odd, and it gradually spread, so I simply cut it off and washed my hands of the matter.

However, now another pseudobulb has developed the exact same reddish blotch, and I don't know what to do. I could keep cutting leaves off, but the problem is probably systemic.

This is a near blooming size plant and has yet to flower, but I wonder if this puts it in jeopardy? I would be so saddened if my birthday plant hasn't bloomed by my next birthday!!

What do you guys think? Attached is a photo of the plant, and a closeup of the questionable area. What is wrong with it?

Edit: WHY my upright photos keep uploading sideways is beyond me, but I don't know how to fix it, either!

[WhiteRabbit]

Hmm ... I had one getting similar spots, but it was growing too cold and damp (no more issues with that since keeping it drier), but if growing indoors, that wouldn't seem likely to be the cause in your case.

Just to help others try to suggest possible causes, can you let us know what temps, light, water this gets?

Regarding photos posting sideways - if you are posting via tapatalk, it seems the proud need to be taken in landscape orientation to post properly.

[astrid]

Originally Posted by WhiteRabbit

Hmm ... I had one getting similar spots, but it was growing too cold and damp (no more issues with that since keeping it drier), but if growing indoors, that wouldn't seem likely to be the cause in your case.

Just to help others try to suggest possible causes, can you let us know what temps, light, water this gets?

Regarding photos posting sideways - if you are posting via tapatalk, it seems the proud need to be taken in landscape orientation to post properly.

I treat all my oncidium types the same. I am trying to water them twice per week now, and gradually increase to maybe 3 times per week because they seem to be thirsty.
I am just scared of watering too much because my first orchids (which were phals and have pretty different roots...) all had their roots rotted off from too much moisture.

However, twice this week I let the plants all soak overnight in water. Otherwise, between waterings they are totally dry. No humidity trays or anything.

This miltassia is the only oncidium type that is having these reddish spots.

I keep all the finer-rooted orchids in a medium bark mix with a fair bit of sphagnum and charcoal in the mix.
These are windowsill plants in a south-facing window, and the winters here are cloudy about 60% of the time. This particular plant is getting light green leaves so I think it's getting too much light and I moved it to the side of the window so it gets more shade.

I don't have a ton of air circulation in my room and I don't keep a fan on, so that may be a problem? minorly?

Anyway, I think that's all the relevant info.

I fertilize when I remember to with a normal concentration 10-20-10 or 20-10-10 fertilizer or something. Something like that. I'm pretty inconsistent about it.

[WhiteRabbit]

What size pot?
Do you use a skewer?

[astrid]

Originally Posted by WhiteRabbit

What size pot?
Do you use a skewer?

I am using a shortened 64oz soup container which I have poked ample holes in, so I am very sure the media dries out totally on a regular basis.

No skewers or anything involved

[terracotta7]

I am glad you asked this question because I have one that looks EXACTLY like that!

I await the answers from others more experienced than I!

[ula]

Too much light, maybe? I used to get these blush patches on orchid foliage and/or pbs of all different genera from leaving them on a south facing windowsill in the spring, where the sun was really too strong for them, so they were getting a bit "tanned". Once I moved them to a shadier location the coloration faded for some, and stayed for others.

[WhiteRabbit]

If your air is quite damp (especially if it's cool, as well), trying a fan wouldn't hurt. If you do have very damp and cool air, it may not need to be watered as much, as well ... I don't know how you are judging when to water - you might try using a skewer or freshly sharpened pencil to make sure that you aren't over watering.

[astrid]

Originally Posted by ula

Too much light, maybe? I used to get these blush patches on orchid foliage and/or pbs of all different genera from leaving them on a south facing windowsill in the spring, where the sun was really too strong for them, so they were getting a bit "tanned". Once I moved them to a shadier location the coloration faded for some, and stayed for others.

Hmm, the plant is getting a bit light green in color, so I moved it to the place adjacent to the window rather than in front of the window. We'll see if the coloration changes.

For me, the sun will make the leaves of my orchids HOT quite fast, so I always screen my windows slightly. I'm terrified of burning my babies!

---------- Post added at 12:59 PM ---------- Previous post was at 12:55 PM ----------

Originally Posted by WhiteRabbit

If your air is quite damp (especially if it's cool, as well), trying a fan wouldn't hurt. If you do have very damp and cool air, it may not need to be watered as much, as well ... I don't know how you are judging when to water - you might try using a skewer or freshly sharpened pencil to make sure that you aren't over watering.

I feel like my air isn't too damp. I never (or very rarely) get condensation on the windows and my plants' media dries out pretty quickly for me.

I'm trying to water the oncidium types every other day or so now (3-4x per week). Before it was just twice per week, but they seem to want more water, and I am getting the feeling they can handle it as my media is 85% bark, 10% foam rock things (perlite but bigger), and 5% sphag.

Their bulbs shriveled for me so I'm trying to plump them a bit. I'm scared of killing the roots as I have done to my phals, but the phals have different needs obviously.

[AnonYMouse]

Watering every other day seems excessive in winter. If it is sitting near a window, it may be too cool to be that wet.

How do you determine how dry the media is? You don't need to soak overnight if the media is established.