Spotting on leaves of various orchids
 

I have some phals and oncidiums and then 1 tiny vanda I have started to worry about and just wanted someone to weigh in on if it's just the leaves or if its actually an issue. A friend of mine suggested the Vanda has orchid fleck. A phal manii of mine has tiny black/brown spots on it as does my oncidium okika. An oncidium yellow Star Golden gambol has some brownish black rings around what looks like a dry spot in the leaf. Please see attached pictures. Any diagnosis and treatment advice would be helpful. Thank you

The Vanda might be getting far too much light. How are you watering and fertilizing it? What are the ambient temperatures and humidity?

The other plants don't look worrisome to me.

The temperatures range from 66 at night to about 70-72 during the day right now. Humidity has been ranging from 50-65% (the air conditioning is running all day to try to keep it comfortable and I added a dehumidifier because it has been very uncomfortable for me). It normally gets a spritz of water mist on the roots in the AM and a good water soak for the roots for about 10 minutes in the PM. It's get fertilized weekly weakly.

I moved it so it will get less light. I wasn't super interested in a Vanda, but I had ordered one for a friend and it came with a friend and she didn't want 2 of them. Any other suggestions?

Do you know the Vanda's name? How long have you had it? Has it made any new leaf growth?

Unless they tell us what fertilizer they’re using and the dilution rate, it’s pretty hard to determine if they’re under fertilized from the photos and info provided.

I’d be more concerned about how much light they may be getting. The phal looks quite lime green, suggesting light levels near the upper end of tolerable, but colors can appear different depending on lighting and focus point of the camera. I don’t grow either of the others so can’t comment on those.

The Vanda looks like it might have a fungal problem due to cold water sitting on the leaves, or just getting too cold. What temperatures has the Vanda being receiving? Tiny seedlings like this can be hard to keep alive under marginal temperature/humidity conditions where that might not be as problematical for a mature plant. And depending on parentage, many (if not most) Vandas like it warm and humid - tropical.

I'm inclined to agree with Dimples that the Phal may just be getting more light than it needs/wants . These are low-light plants. (For the record, I fertilize very lightly, about every 2 weeks or less, half teaspoon per gallon, and have nice robust green leaves. Orchids need very little fertilizer, in my experience. There have been times when mine didn't get any for months and showed no ill effects... maybe grew a little more slowly but no drastic effect) . The Oncdium? They just tend to get ugly leaves. I don't see anything to worry about.

I will get back to you on the Vanda type. I can't remember exactly which it is and when I got the 2, I mixed up the tags so I am not sure if the tags are right. I will let you know which 2 tags I have at home though. I got the Vanda in April and I do see a tiny start of a leaf or 2 down in the middle. I also am just now starting to see any root growth. The plant has just existed since I have gotten it.

@manurespreader Most of my orchids get watered once to twice a week (depends on type of ochid and pot size). The Vanda is the one that is getting watered once to twice daily since it is bare rooted. I am watering with quarter strength fertilizer once a week.

---------- Post added at 05:22 PM ---------- Previous post was at 05:17 PM ----------

And just adding I use MSU fertilizer for RO/Rain/tap water. Here is what's in it.

Macronutrients:
Total Nitrogen 13% (Nitrate Nitrogen 12.5%, Ammoniacal Nitrogen 0.7%)
Phosphate 3.7%
Potash 15.9%
Calcium 8%
Magnesium 2.6%

Micronutrients:
Iron 0.177%
Manganese 0.088%
Zinc 0.044%
Copper 0.044%
Boron 0.018%
Molybdenum 0.018%

I also add a little bit of iron since I use the same water for my violets, and occasionally some quantum plant probiotics and some seaweed extract.

I also use MSU Cal/Mag (with RO water). When I get around to it. Of all the cultural factors, it's the least important... get everything else right (watering, medium, air circulation, temperature, light) then the fertilizer part is "fine tuning". Remember, epiphytes have evolved to live in a very nutrient-poor environment. All they get in the way of fertilizer is what might dissolve in rain water from rotting detritus and whatever else may be in the forest canopy. Over-fertilizing orchids (especially if everything else isn't optimal) can lead to a lot more damage (burned roots, black leaf tips, or worse) than under-fertilizing, that at worst just might slow them down a bit. Too much nitrogen might encourage growth if not over-done, but tends to inhibit blooming. So you don't need "bloom boosters" to facilitate blooming, just reduce fertilizer concentration and frequency. (Take a look at the links in my signature line to see what happy, mostly-ignored, orchids can do)

The Vanda stays the same Temps as my other orchids.....ranging from 66-72 degrees F and humidity ranges from 50-65% or so. I live in SW Virginia. Maybe i can hang it outside on my patio. Its been super humid and very warm during the day (highs in mid 80s to mid 90s and lows in the high 60s to mid 70s and humidity ranges anywhere from 50-70%). I try to keep water off the leaves and just on the roots. The spots showed up about a month after I got it. If it doesn't live, it's not a huge loss to me. I got plugs initially of alot of oncidiums and they can with extras and while I was excited when I got all these little friends, my collection grew very quickly. I love my oncidiums and really didn't expect to add a Vanda to it.

I have been considering moving all my phals to a different shelf... I have some grocery store phals that I don't feel like get the light they want since the sit in my window sill and some phal species that probably get a little more than what they actually need. I have considered putting up some floating shelves to hold them and a lower level light to just help keep them all happy. That way my shelves they currently live on can be for my higher light loving plants.

I am so happy that this stuff doesn't seem to be anything to be super concerned about. I love my orchids and would be sad if they were wiped out by disease. Thanks!!!

That's on the cool side for most Vandas. Your outdoor temperature and humidity are ideal this time of year - protect from direct sun. Bring it in when night temps get much below 60 deg F (in the fall) . In fact, if you have a shadier spot outside, the Phals would enjoy it too. Your indoor temps are much more pleasant for humans than the hot muggy outside (I would even consider it chilly, if I were visiting your house I would be wearing a sweater...) , but for the warmth-loving tropical orchids such as Phals and Vandas, they love hot and muggy. The Vanda needs much more light than the Phals, of course, but still not direct sun. If it rains on them, even better.

Water on the leaves is much less of an issue (or actually is a non-issue) if it's warm and there is good air movement - which Mother Nature provides. When it is warm, I water in the evening with no problem. Roots can absorb the water in the cooler air of the evening with slower evaporation, and water on leaves isn't a problem. Of course when it's cooler (fall, winter and into spring), I confine my watering to the morning so that everything is dry by evening.