Spots on my phal - Orchid Board

malteseproverb · #1 03-07-2018, 02:36 PM

Last week I noticed some small raised white bumps on a leaf of my phal, which is putting out two spikes right now. Then today I saw a dark pitted spot on another leaf. What is going on with my plant? Any one have any insight? I water around once a week and it sits in an east-facing window. It's been very dark and gloomy recently. It sits in a clear pot and the roots look fine.

WaterWitchin · #2 03-07-2018, 02:44 PM

Google spider mites and scale. See if you think it looks similar to what you're seeing on the plant. That's what it looks like to me.

malteseproverb · #3 03-07-2018, 02:51 PM

I've had scale before, it never affected this plant at the time, but I treated it with the same stuff. I'm not seeing any scale, and I looked in the pot. I don't see any evidence of mites, even on my plants that would normally attract them if there were an infestation. It's definitely possible though. It's so easy for bugs to hide...

rbarata · #4 03-07-2018, 03:04 PM

Rub gently, under the leaves, a piece of white cotton embeded in a solution of water and alcohol.
See what comes from that.
Is the cotton red or brown?

If so, it's mites.

estación seca · #5 03-07-2018, 03:12 PM

Any chance you splashed cold water on those leaves? That can cause trouble like this.

rbarata · #6 03-07-2018, 03:14 PM

Quote:

Originally Posted by estación seca

Any chance you splashed cold water on those leaves? That can cause trouble like this.

Yes, that window glass covered with snow caught my attention too.

malteseproverb · #7 03-07-2018, 03:30 PM

Splashed cold water... well I watered on Sunday, and I put it in the tub and use the shower head, and I use lukewarm water, but I guess it becomes cold with time, perhaps before it can dry? I run a fan and the room doesn't get below 60F. I will do the mite test. It is snowing here today, but that's not typical here. It is still winter though and therefore not a balmy environment. What does the cold water do?

---------- Post added at 02:30 PM ---------- Previous post was at 02:21 PM ----------

Did the cottonball test, no brown or orange. The other thing I was thinking about is a problem I've previously had with phals after a long period of cloudiness, which is that when the sun does come out on one or two days, it burns the leaves. And this did happen this week after 2 weeks of nonstop rain. This has happened to me before, to the point where I lost a phal last year. And maybe that combined with the fact that the sun is getting stronger now that it's March... but I'm not sure about the brown spot.

estación seca · #8 03-07-2018, 04:13 PM

60 F / 15.5C is far too cold for a Phal. If the leaves were that cool, and wet, and there were a good breeze, the evaporative cooling would take the temperature even lower. That could cause this kind of leaf damage.

Some people insist they can keep Phals alive with temperatures like this, but that's just random luck. It will run out before long.

malteseproverb · #9 03-07-2018, 05:45 PM

Ah, I didn't know that. Would that cause the other discoloration or just the brown spot? I used to live in an apartment where the heat was always set to 70 degrees in the winter and I wasn't billed for it so I never ran into that problem before (many others though). I had this plant there for a few years but it's actually done better in my new place. Temps currently get to 70-75 in the day if the sun is out, but we only run the heat if we're home so for a few hours in the evening and it goes off at 11pm.

And here I was worrying about my brassavola nedosa, bulbophyllum, etc. in terms of temps. I wonder what I can do to mitigate this in the future. I'm not about to start paying more for heat. Would a heat mat work or would that not put out enough warmth to help the leaves? Other than this discoloration, this plant produces vigorous growth, tons of roots and flowers.

rbarata · #10 03-07-2018, 06:02 PM

Many people here with similar issues as yours use heat mats with good results.