My Miltonia bulbs turning color & a leaf died? Help

[PasoTrailRider]

I am new, only had orchids for a year now. My Miltonia started with a leaf turning yellow a couple weeks ago. I had it in lava rock and noted it was not happy, displaying it's leaf turning yellow as if a mag deficiency (halo first, then turning yellow). Live in Ohio and it is cold and realized the rock was keeping her colder and re-potted her in bark and moss about a week ago. However, she is getting worse fast. The top of the bulbs now turning color... Help her and me please.Miltonia spectabilis v moreliana 'Royalty' AM/AOS - Google Photos

[SouthPark]

Growing in lava-rock or bark is just fine.

You correctly sensed that temperature may be associated with the issue, and it most likely is associated with the issue. If the growing environment gets very cold, and the temperature drops to a level below a recommended safe range for the orchid, then issues can arise.

A warming mat (with temperature control) that just keeps the base a little warm (not hot or super hot or anything) will likely help here.

The orchids generally do well when given suitable temperature, light level (and light duration), and good air-flow through the pot and media and around roots. Just work towards achieving these conditions, and the orchid should recover. Also - have some fungicide waiting in the wings - in case it's needed, such as agri-fos systematic fungicide 16 ounce, mancozeb, and thiomyl (cleary's 3336).

If the orchid isn't getting enough light, then a broad-spectrum light placed near the plant (but not too close as to cause plant damage) will help too, as I can see that there's snow outside, and over-cast. But if in general you get a decent amount of light coming in during winter time, then that might be ok too, as you mentioned you had been growing for approximately a year.

[PasoTrailRider]

Thank you, thank you!!!!

[Dollythehun]

Is that discolored pbulb soft? How much light? How often are you watering? I'm in your neighboring state, so I have an idea of cold (although not like usual).

[PasoTrailRider]

No, the bulb is not soft yet, but this happened so so fast. The discoloration within 48 hours... The light is west window with south windows as fore light. The get soaked once a week or when moss appears dry. Humidifier is at about 46 percent. With cold snap the room is in mid 60's...

[Dollythehun]

I asked because they look "blushed" from high light. I have some like that. What are your temperatures? You water how often? From the pictures the plant looks to be in good shape.

[SouthPark]

Originally Posted by PasoTrailRider

No, the bulb is not soft yet, but this happened so so fast.

The roots look quite ok. The circled region looks ominous though, as if some rotting is occurring there.

An application of systematic fungicide (spray) on the plant's bulbs and leaves might be necessary. Good air-flow all around the growing area will benefit the plant too.

[PasoTrailRider]

The only change in light could be reflective from snow?

---------- Post added at 10:12 PM ---------- Previous post was at 10:09 PM ----------

I ordered some fungicide tonight from Amazon, will be here tomorrow. Thank you so much!

[PasoTrailRider]

I want to thank all of you for your help!!!! I will update you all either way in few days. Delivery of fungicide will be today, will apply... Meantime, at night, moving her away from the window (despite them being Pella double pane) may still be too cold and the combination of everything hit her. I also love the idea of the warming pad under the plants to keep them from stressing the cold. Thank you for that advice! You all are great!! Thank you, thank you. Tina

[WaterWitchin]

It looks pretty good to me overall. Especially after a year in your culture. If your "cold snap" is bringing your room temperature down into the 60's, that's getting toward night-time temp. Daytime range is max 75-85F and night 60-65F. Over time they can tolerate a bit cooler. Humidity of 45% is borderline in my particular culture of them. Miltonia lives in a pretty humid environment.

I'd watch the discoloration on the pbulbs. Could be blush of color, as Dolly says, or possible rot as SPark pointed out. I can't tell which from the pictures. Time will tell you fairly quickly.

Miltonia can stand more light than Miltonopsis, so doubtful snow glare is the issue, unless sun is directly hitting it for hours a day.

---------- Post added at 08:48 AM ---------- Previous post was at 08:47 AM ----------

PS If I haven't said it elsewhere, Welcome to the Board!