Hello! I'm new in the orchid world. Have this Phal orchid and it was doing great until now. I just noticed these small spots in some of the leaves and I have no idea what it can be. I see no bugs of any kind in the plant and it seems healthy to me. It is even producing new leaves and branches but these spots don't look normal to me. Should I worry about it? Could it be a fungus? Any insight and help would be very appreciated :)

Those look like the oldest leaves. They have served their purpose and continue to yellow until they drop off (or you cut them off) the plant. As long as you have new leaves, all is good.

Yes! and welcome!
Perhaps you might look around and peruse the NUMEROUS existing threads on Phals! And perhaps even include your questions there, so we are able to help you better, as most people will look at existing threads.

I am alarmed to see this "damage" and I do not like it!
At first I was thinking insect damage on the underside of the leaf eventually making itself visible on the upper surface of the leaf.
BUT in your last image of the underside of a leaf, between the 2 spikes or inflorescences, those irregular yellowish markings look like it could be a virus! And if it is, that is bad because there is no cure for it.

We have no information as to the light, the temperature and watering details but I am concerned all the same.

DaisyI said:

Those look like the oldest leaves. They have served their purpose and continue to yellow until they drop off (or you cut them off) the plant. As long as you have new leaves, all is good.

Thank you for your input Daisyl. I hope you are right and my orchid will be ok.

BigBill said:I am alarmed to see this "damage" and I do not like it!
At first I was thinking insect damage on the underside of the leaf eventually making itself visible on the upper surface of the leaf.
BUT in your last image of the underside of a leaf, between the 2 spikes or inflorescences, those irregular yellowish markings look like it could be a virus! And if it is, that is bad because there is no cure for it.

We have no information as to the light, the temperature and watering details but I am concerned all the same.

Thank you for your input BigBill I am very concerned about it because it's the first time I see something that seems abnormal to me in my orchid leaves. I have had it for almost an year and never had a problem until now.

I have inspected the orchid thoughrouly and haven't seen any kind of bugs on it. I am very afraid it could be a fungus or like you said a virus. I am not sure how to tell the difference though.

I inspected all my other orchids too now and there's another Phal with the same type of spots in one of its leaves but just four little circles. That is what is making me wonder if this could be a serious problem.

To give you a little more details, the temperatures I keep my orchids right now range from 65 to 70 degrees. Humidity usually between 45-55. They get a lot of bright light but they are not in a windowsill and don t get any sun directly on them. At this time of the year, I usually water once a week or twice if the pot feels very light.

I think that your growing conditions are fine.
Any insect damage I can think of does not look like what your images show. Same for fungal or bacterial issues. Hence my concern. It could be insect damage from the underside of the leaves but then those yellow kind of circular/oval stuff I see does not look like insect damage. At least not that I can recall in all my 45 years.
It is not heat stress or cold stress plus your temperatures are fine.

I just found a similar spot on one of my orchids. When I was able to see the back of the leaf I did find scale.

On what type of orchid Carol? You usually see damage like that coming through from the other side of the leaf on thin leaved orchids like Oncidium and Dendrobiums. Phalaenopsis not so much.
But those yellowish areas on the underside of the leaves between the inflorescences are of very irregular shape. That doesn't not happen with an insect attack, especially on a thick leaved orchid plant.

Mine is a Cattleya with huge, thick leaves. I think it was the only one in the shack with any live scale.

BigBill said:I think that your growing conditions are fine.
Any insect damage I can think of does not look like what your images show. Same for fungal or bacterial issues. Hence my concern. It could be insect damage from the underside of the leaves but then those yellow kind of circular/oval stuff I see does not look like insect damage. At least not that I can recall in all my 45 years.
It is not heat stress or cold stress plus your temperatures are fine.

I am quite concerned it may be a virus now so I am thinking about getting it tested either by getting a testing kit from Agdia or sending it for testing at a lab.

Well, if I saw that, I would toss it but then again, I have 100 plants. I would not want to keep it around.
You have to sterilize everything that comes in contact with the plant, tools, Hands, etc.
Phalaenopsis are easy to locate and buy, I would not want to chance it. There is no cure which I think is the best reason to toss it.

If the plant is valuable to you, please get it tested. Keep it isolated from any other orchids you might have.

Make sure you wash your hands after handling it. Sterilise tools throughly (flame them i.e. with a butane torch, or you can soak them in isopropyl alcohol or trisodium phosphate for 15-20 minutes - a simple wipe with alcohol is unfortunately not enough to kill the common Orchid viruses).

It might sound paranoid, but if you have valuable plants, it's far better to be overcautious than not.

If you do decide to try and save the plant, do follow the advice given here about sanitation and I would add that it would be wise to remove the plant from the pot and carefully clean off all the potting material. Repot using fresh potting mix and a sterlized pot.

Are the yellow spots on the old leaves only? If it was a virus, wouldn't the entire plant be affected, including flowers? Isolate it and see what develops, if anything. Use your sanitary practices (but you should use those as a matter of course).

If it is a virus, its not in the potting medium but in the plant tissue. Virus are spread by vectors in an exchange of bodily fluids - the same way we get viruses. That could be an insect but most likely a human. Wear disposable gloves and sterilize surfaces and tools between cuts and plants. A 10% bleach solution will kill the virus too, but it sure plays havic with your gardening tools.

DaisyI said:Are the yellow spots on the old leaves only? If it was a virus, wouldn't the entire plant be affected, including flowers?

Unfortunately not, Daisy. I've had Cyms test positive for a virus that only showed symptoms on a couple of leaves. It really depends on the virus (some are quite variable in the degree of symptoms) and the strength of the plant (plants with good culture and strong virus resistance are likely to show far fewer symptoms).

DaisyI said:Are the yellow spots on the old leaves only? If it was a virus, wouldn't the entire plant be affected, including flowers? Isolate it and see what develops, if anything. Use your sanitary practices (but you should use those as a matter of course).

If it is a virus, its not in the potting medium but in the plant tissue. Virus are spread by vectors in an exchange of bodily fluids - the same way we get viruses. That could be an insect but most likely a human. Wear disposable gloves and sterilize surfaces and tools between cuts and plants. A 10% bleach solution will kill the virus too, but it sure plays havic with your gardening tools.

The spots are both in old leaves and new leaves. The older leaves look the worse though. The plant hasn't flowered since I discovered these spots but it is growing little branches now and seems that it may want to flower at some point. I'm curious to see what the flowers will look like if it gets to bloom to see if they look different than before.

I would like to keep the orchid if I can since it was my first one and a gift from a very dear friend. I fear for my other orchids though if it is indeed a virus. I have kept it separated from the others once I found the spots and sterilizing everything with alcohol to try to prevent more propagation of whatever these spots may be.

Alcohol won't kill a virus. Sterilize with heat or bleach.

Viruses are spread by exchange of bodily fluids. That means if you cut a dead leaf off an infected plant, or break a root or clip an old flower stock or... And then move on to another plant without sterilizing your hands and tools and work surface, you will pass it on to a new unsuspecting plant.

The reason for separating the maybe infected plant from the others is viruses are also spread by sucking insects (mealy bugs, scale...).

You can keep your orchid, just be extremely careful. When I suspected one of my orchids had a virus, I found someone at my orchid society meeting willing to sell me one test. It very easy to administer.

Wanted to share that I ended up getting the orchid tested for virus and the results were negative to my surprise still going to try to figure out what those spots are.