Possible Sunburn - You be the judge :)

[joejack]

Problem:

This has been an on going problem since I purchased the plant in August. Me not knowing much about orchids did not think anything of it as the plant over all seemed healthy. Then I found this board after being a bit more curious about how to care for the plant.

After reading a bit I believe it is Sunburn as there is a half dozen or so black spots that do not seem to spread.

I will let you all be the judge as this is my only and first orchid.

Plant Care and Description: Zygo. Mackeyi

General Description of plant: Two prominent sudo-bulbs with leaf growth of 12" or larger. Two newly grown with leaf growth of about 5-6" (one has a spike which has formed seemingly right out of thin air, was a very rapid growth spurt.) And finally a new growth that I just noticed yesterday that is about 1.5" long.

Care: Watering about once a week depending on if it needs it. Just kind of playing it by feel. Norman's fertilizer is used every two weeks (but I am sure it is too much) messure is about 1/4 teaspoon with about 15oz of water after initial watering. I have done no flushing as that technique is new to me and will begin next water session.

Lighting: The plant currently sits on my windowsill facing the rising sun (my window faces NE) and receives light till mid day when the sun begins to creep over my house. (about 7ish till noon)

Color: medium/light green (with of course the dark splotches ).

Medium Planted In: Original Medium provided by orchids.com. I believe it is that Moss that starts with a "P" and some small to medium sized bark chips. As I have not re-potted the orchid I am not sure what else might be down there.

Thank You for all your help,

Joe

[Ross]

Don't know much about Zygos, but I know quite a bit about sunburn (both on plants and on people). If the tissue was burned to the point it turned brown, those spots won't recover. But you haven't necessarily damged the plant to the point of death. The general rule of thumb is that if exposed to very high light (higher than it is used to) an orchid will exhibit reddish foliage or reddish margins on the leaves. Beyond that point, death of leaf cells occurs (they fry!) and turn brown. In most cases these are cosmetic blemishes (as long as plant ir removed from the overly bright light). This can happen with artificial light as well as sunlight. I have proven this with several of mine (pushed the limits by placing a few too close to lights). You can introduce your orchids to bright light over a period of time (months, in some cases) but most damage occurs when a plant is moved to a bright spot over a 1 day period after living (or existing) in low light for months or years.

I would back off the light (say to an east window, for a few weeks, then move it to a south window, but not right against the glass - perhaps a screen might cut down on light. Then up the light after a few weeks by moving it closer and letting it get a little sun. Does all this sound familiar? Like getting a sun burn first thing in the spring? Small doses will do no harm - extended periods will burn the leaves. Hope this helps.

No need to repot just because of this incident. That shock might be too much on top of the burns.

-------------------------

I just re-studied the photos and missed the part about the moss. Is it actually planted in moss (that's sphagnum, by the way) or is the moss just on top? I ask this because it's common for stores to sell orchids top dressed with moss which coveres up the conditions of the potting mix. Maybe your question about sunburn diverted my attention because a Northeast window can't reall provide that much light, normally. I'm starting to think rot.

[Phantasm]

I'm not a big zygo grower (only a couple) , but it doesn't look like sunburn to me. The main concern in my opinion is growing in that moss, you really have to pay attention to it as it breaks down. Norman's grows all of their plants in this stuff, so it must work for them. The few plant I purchased from him, I immediately repotted in my normal bark based mix. That's my comfort zone and growing in media you don't use is always dangerous.

[Lagoon]

Hi Joe,

Those spots don't look like sunburn to me.
I've got the same kinda thing going on with 1 of my oncids right now. I found that spraying with a good fungicide helps stop the spread.

Welcome to the OB

[joejack]

Thank you all for the information. I will look into getting a fungicide this weekend.

As for the media it is currently resting in... It is the sphagnum not "P-something" as I had originally mentioned. Just dropped the "S" when thinking of the word. It seems to be 3/4 sphagnum and then a handful of small wood chips. Did not want to do much digging around so as not to damage any roots, but that is my best guess.

@ rsfrid : I monitored the light pretty much all day as I only had one class and it does not seem to get overly bright in that area. So I am going to run with the rot assumption.

Thank You,

Joe

[GlennGibson]

Hi Joe

I am new to growing orchids and have one year of experience. I have two Zygopetalum Mackayi (Mackayi x Aussir Quest). Like yours they too have the same brown spots. I glad to tell you that it’s nothing to worry about.

This seems to be a common problem. I purchased mine over a year ago from Santa Barbara Orchid Estates (Santa Barbara Orchid Estate Home Page) When I purchased them they brought to me attention the spots, they had no idea what causes the spots. I have done nothing to prevent the spots...because it futile. I’ll give them a call tomorrow and see if they can give me any more information. I’ll keep you posted.

The plants are healthy. In fact they are in bloom now. Last year they had only four flower spikes, this year they put out ten spike.

Go to my gallery I'll upload two pictures 01 Zygopetalum Mackayi with Brown Spots & 02 Zygopetalum Mackayi with Brown Spots.

Hope this helps.......

Glenn

[Ray]

1) If it's the species, the specific epithet is in lower case - Zygopetalum mackayi.

2) That is bacterial or fungal damage, definitely not sunburn.

Zygo leaves are quite thin and fragile, and the slightest bruising leads to such a topical infection, and as Glenn mentioned, there's very little that can be dome about it. I've had zygo's for about ten years or so, and find they look their best when the are placed well in the GH and never touched.

[GlennGibson]

Good Morning Joe

I called Santa Barbara Orchid Estates and talked to Mike. He said the spots are very common. He indicated that they are not due to sunburn, bacterial or fungal damage. According to him no amount of fungicide or anything else will change their condition. He also said that they feel this is more a genetic problem and that Zygopetalum mackayi seems to be more prone to this condition than other members of the zygo family.

As Ray said in the above post.... the leaves are thin and fragile and lend themselves to bruising.
After looking at your photos I realized that my two plants have more spots and yet they are otherwise healthy with more blooms this years than last. I grow my orchids outside. Here in southern California we get fierce Santa Anna Winds 25 to 60 mph. This is probably why I have more spots and bruising than you. As Ray indicated.. Find a the right spot for them and touch them as little as possible. I’m certainly going to try his advise.

If I learn more I’ll let you.

Wishing you the best.

Glenn

[savor]

Joe,
The spot low on one of the growths resembling a small bar may be a bruise. The spots towrd the end of leaves look more like spots from uneven watering. They might also just be genetic. If you want to inquire further, I suggest you google JEM Orchids at their new Hawaii locations. Gene Monnier could tell you exactly what it is and how to avoid more spots.
Good luck,
Lee

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