Need Help with black spots on Vanda (PICS) - Orchid Board

cbloveday · #1 03-24-2009, 09:49 PM

I have started to notice black spots on my vanda. They seem to be getting worse. They are concentrated on the top leaves. I believe it is a fungus and need a vanda experts opinion.

Growing conditions are under indoor light. I water only the medium daily or every other day. Roots look like they are propagating and firm. I have only had 2 months so no blooms yet. Temp is 70-75 during the day and 55-65 humdity. I have humidifier in room. I fertilize very lightly every watering with Hausermann's Fertil-ade 15-5-5. I have physan 20 and was wondering how I should apply it if you believe it to be fungus.
Should I use diluted strength like 1 teaspoon to gallon and spray leaves?

Also the lower leaves have a chalk like appearance.

Please help, this is my only vanda!!!!

cbloveday · #2 03-25-2009, 07:54 AM

bump for help

cbloveday · #3 03-25-2009, 08:01 PM

27 views and no replies?

Gin · #4 03-26-2009, 09:32 AM

Hi , I think the white deposits are from the water mine has a lot of lime in it and does the same , or from Fert. salts. I would be sure to water the roots that are out of the pot too .
About the spots not sure about them it would not hurt to use the Physan, as you said a teas. to a gallon . If they are outside I would suspect some type of insect damage . Gin

cbloveday · #5 03-26-2009, 02:15 PM

Quote:

Originally Posted by Gin

Hi , I think the white deposits are from the water mine has a lot of lime in it and does the same , or from Fert. salts. I would be sure to water the roots that are out of the pot too .
About the spots not sure about them it would not hurt to use the Physan, as you said a teas. to a gallon . If they are outside I would suspect some type of insect damage . Gin

Gin,

Thanks for the reply. I wiped the blades down and sprayed physan on the plant and soil also did the all the other plants. I will watch to see if spots continue to emerge or if the chalky residue returns. Keep you all posted if interested. Thanks again.

Curtis

Gin · #6 03-26-2009, 05:35 PM

You are very welcome

sorry you did not get more replies, it is always good to get other opinions .If it is the water the white residue will return.
I went to rain or Ro. water because of that, in time it seemed to dry the leaves out . I am interested to see how things go .

Don Perusse · #7 03-28-2009, 12:25 PM

The white film on the leaves is probably like Gin said, either calcium in your water or salts from watering. Just flush with plenty of water every month. The little black spots are quite common with the vandaeous family. But be assured it won't hurt them. I have some that have a lots more than you are showing. I really don't think it is a disease or fungus but using Physan is always good idea in the greenhouse and on your orchids.

vandavixen · #8 03-28-2009, 02:54 PM

I'd say it is very normal to see those tiny spots..However you may sometimes have been misting and the sun or lights if strong enough can burn from the reflection of the water left on the top of leaves but it really does not look like burn marks.. and I forget right now if you mentioned it is near a window..if so it can be burn marks . I also tend to believe it is a trait inherited of this particular Vanda.
If they are real tiny tiny it is normal I believe.

cbloveday · #9 03-28-2009, 06:09 PM

Quote:

Originally Posted by Don Perusse

The white film on the leaves is probably like Gin said, either calcium in your water or salts from watering. Just flush with plenty of water every month. The little black spots are quite common with the vandaeous family. But be assured it won't hurt them. I have some that have a lots more than you are showing. I really don't think it is a disease or fungus but using Physan is always good idea in the greenhouse and on your orchids.

Thank you, I have been using physan on all my plants the last few days.

Quote:

Originally Posted by vandavixen

I'd say it is very normal to see those tiny spots..However you may sometimes have been misting and the sun or lights if strong enough can burn from the reflection of the water left on the top of leaves but it really does not look like burn marks.. and I forget right now if you mentioned it is near a window..if so it can be burn marks . I also tend to believe it is a trait inherited of this particular Vanda.
If they are real tiny tiny it is normal I believe.

It is in my grow room under lights. Never misted before.
Starting using physan in water and misting with diluted physan. I will monitor it closer. Thanks for all of the replys. I will keep a closer eye on this.

sprater16 · #10 03-29-2009, 01:36 PM

Hi there. Just had to throw this out there. In the third picture, the top leaf that looks like its been sprinkled with tiny dots.... I notice this happens to my vandas/ascocendas if I hang them too high in my shade house. I asked my local supplier about it and was told it's not sunburn per say, but rather 'freckling.'

Vandas are a lot like people in this respect... when people are exposed to fair amounts of sun over long periods of time, say their lifetime, natural variations in pigment deposits are darkened, creating what we know as freckles, sun spots, age spots, etc. Your vanda simply has some freckles from being exposed to the high light levels necessary for their culture. As mentioned by vandavixen, some vandas are more prone to this type of spotting due to their genetics.

I personally have found that my ascocendas are more prone to this spotting behavior than vanda x vanda crosses or species, likely due in part to the original ascocentrum parent. Ascocentrum, at least in my experience, are almost always covered in reddish/purple spots. There's a thread on this phenomenon titled 'Ascocentrum ampullaceum' started by Toddybear.

So, my verdict... your plant is fine but keep up with the physan for a bit longer just in case. Hope that helped.