Black spots in Vanda leafs

[Josh]

Hello,

My new Vanda came with these black spots in a few of its leafs. Is this some kind of known disease? Is the plant at risk?

Thank you for all the help.

(This is a very good advice I got and now my Vanda is healing)
FROM:

digitalgate
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the black spot can caused by secondary fungus infection, while nothing serious it is a permanent mark. You primary problem can be mite infection(or any small biting insect). So alternate weekly neem oil with other pesticides should keep the pest to a minimum. you can keep the fungus in check using carptan, thiram ..

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Yo Josh:
I have a similar problem with my Vanda Sanderiana alba. Its been with me for quite sometime, flowers twice a year and sirvived many apartment movings and I wasnt aware of the black spots until I started reading posts in here by members. I started examining my plants for any discolorations, spots, anything that is making it ugly. I have seen some healthy vanda pictures posted and they are perfect in beauty. I decided to clean all my plants with alcohol and wipe them all with neem oil. I dont want any bug to come near it from now on nor do I like any yellow or black spots in any of them...I even bought virus testers and tested all of my plants. Thankfully it is all negative of virus! So I wont incenerate not a single plant so as not to contaminate the others.
I buy my virus testers at Ebays for $10 each and go to my local orchid supply store for fertilizers, pest control chemicals, gadgets, pots and mediums. I even bought from a member here some glass planters he bored holes on and it is a good way to replant my phals...I can see and monitor the roots through the ornamental fancy glass.

[Josh]

Thank you for the reply. I just recently purchased this plant, it is here not even for a week, so maybe those marks come from bites from insects at the greenhouse where I purchased it? Hopefully in here it will be clear of those pests. I have Neem Oil that I use in other plants and could apply it on the Vanda, but would rather not if possible to avoid. Should I only use it in case I see some bugs on it? Any further advice would be appreciated.

[orchids4me]

Going to move up your thread so it doesn't get missed

[digitalgate]

neem oil comes with its own set of problem. How you spray the oil is critical. When you have a concentrated spot on the plant. It will burn the plant. So it is good to shake the content of sprayer when you spray. you only need 1.4 ml per litre of water Or 5.18ml per gallon of water. Even through it is thought to be bactericides, it gives me bacteria problem. Good news is nothing serious and easily solved with physan.
You should spray it regularly to prevent insect problem as pest like mites is almost impossible to get rid of. At least in my case, tropical weather ,exposed to the element . surrounded by trees.

[Josh]

So Physan is what should be used to treat those black spots in the Vanda? But are the spots a fungus or insect bites?

[pikkumyy]

hey guys, one of mine has the exact problem, but it hasn't seemed to have done anything, here is a pic, you can probably see the spots

[digitalgate]

insect problem look similar to normal leave except for the yellow spot followed by black spot a few days down the road. If it does not spread, then it is fine. IF it does spread , fungus just take over. This can be caused by any small biting insect.
Fungus problem just turn turn black spot right away without any marking caused by insect. There is a slight difference. Bacteria problem is another. It may not caused soft rot, some time numerous white pot / yellow spot turns black as it progress.

Thanks digitalgate I followed your advice and my vanda is healing ...I see fewer spots now that I have wiped it with the chemicals. I never examined it closely ever since I started caring for it; but until now. I am vigilantly inspecting every leaf of all my plants...I dont like bugs, mites or bacterias...I think I must quarrantine plants I buy grown in open air, and we dont know the conditions of how they are travelling by air and by land. Those warehouses where the postal truck dumps them might have viruses from rodents that roam about...I will resarch on what is the best sterilization of plants that have just arrived in a box, then transplanted to a new and clean medium and pot.

[Brooke]

"postal truck dumps them might have viruses from rodents that roam about"

Don't worry, rodents don't carry orchid viruses

I use a systemic insecticide every time I bring a new plant just in case there are hitchhikers on a plant that looks clean as a whistle. When I repot I scrub all the foliage with soap and water to make sure there are no eggs hidden in dead bracts or crevices of the plant.

To date I have never had an infestation from a new orchid.

Brooke

[willowbanks]

Josh and Anky, both your plants look more like mechanical damage caused over time by the wire hanger rubbing on the leaf.

Pikkumyy, your little spots are natural pigmentation from the species in your plants background.


Bill

[pikkumyy]

thanks bill, so which side would that have come from?

[willowbanks]

Three generations back when Ascocentrum curvifolium was introduced.

Bill