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Old 01-11-2005, 07:40 AM
 
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Default Help -- black spots & sick plant

Can someone help identify what might be wrong with my phal & what to do
about it? It's had a little black spot on the edge of one leaf for
quite a while, & there's a nick in the leaf in that spot, which is a
little bigger & along the edge now, & the spot is very hard, & black.
I've suddenly discovered that the plant has developed a lot more black
spots, over new & old leaves both. Some are down at the base of the
leaves, & a few are right in the middle of an otherwise healthy looking
leaf. However, it's starting to lose colour & the leaves are getting
some icky paler green tending to yellow; this has happened since last
watering a few days ago.
The spots are 3 or 4 mm across, uneven, hard, raised & bumpy. Looks
like some sort of... ergot-y thing, I don't know.
It's currently in bloom & has been since sometime in the summer. The
flowers are ok, except for one or 2 little spots that you might get
from water (?) or abrasion, on an older flower. The roots look fat &
healthy too. This plant is, I think, generally on the dry side because
of its location & the very loose potting mix & small clay pot, but this
month has been very dark & gloomy -- I did try to spread out the
watering more than usual, & I usually dry the leaves before I put it
back, but maybe I left it a little damp? I may have a tendency to
overfertilize but I'm working on it... In any case it looks like
whatever, has got into the plant's system now.
I have looked up my orchid books. Says sunburn can cause sunken black
spots, & rot causes soggy spots. Fungus causes "spotty leaves."
Nothing about raised black warty things.
Then I did an archive search here & read some of the 219 results that
"black spots" returned. I'm still not sure exactly what it is or what
I should do with it. This is "Dad's" plant (i.e. he picked it out &
wanted me to buy it, but I get to look after it) & he will be very,
very disappointed if it croaks. I put cinnamon on it in a panic,
sprinkling it liberally around the crown & on all of the spots that it
will stick to, although some are on the undersides of the leaves. What
else can I do? Does anyone use the garlic tea one of my books
recommends (1 crushed clove in a litre of water)?
I really don't want to lose this plant. Any ideas would be most
appreciated.
Thanks!

Alison

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Old 01-11-2005, 08:37 AM
Munir
 
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Default Help -- black spots & sick plant

Hi there. From the description, I understand the problem to be a
proliferation of raised, black spots and also yellowing leaves. I
checked the troubleshooting section of my best orchid book and here's
what I came up with:

a) Insects & Mites: scale insects appear as brown, white, or grey bumps
on leaves, stems, and flowers. Severe infestations can cause yellowing
and stunt the plant. Remove scale using a swab dipped in 70% denatured
or rubbing alcohol.

b) Diseases: fungal infections often create black spots but they are
sunken--not raised. Black spots could also be caused by a virus, but
there's no treatment for that. And it doesn't say they're raised
either.

c) Problems in the Environment: This section shows a leaf with raised,
black spots and states that the condition resulted from underwatering
(underwatering that attracted scale to the leaves). Later in this
section, it says that symptoms from too much fertilizer include burnt
leaf tips. And still later in this section, too much light results in
yellowing of the plant.

Based on the troubleshooting guide, it sounds like the plant is
expressing multiple environmental issues. Underwatering may have
attracted scale that shows as the symptom of raised, black spots.
Overfertilization shows in the burnt leaf tips. And excess light shows
in the general yellowing of the plant.

The response of treating the scale with denatured alcohol, watering a
little more frequently, fertilizing less often and/or with weaker
solution, and reducing the amount of light would help this plant.

Disclaimer: I'm not a pro. So you might want to get a second opinion
before taking action. I've read about 7 books on orchids but this one
is my favorite and contains the troubleshooting guide I used to write
this email: Ortho Books Complete Guide to Orchids. They sell it,
surprisingly, at Home Depot in the garden section. I know--Home
Depot--but it's really more informative, accurate, and current than
books I've found and read at other boutique shops and at the library.

Hope this helps! Let us know how it works out.

-Munir

P.S. I have six orchids and just discovered, earlier today, that three
of them--all from the same vendor--are suffering from some infestation
and rot. The reason, I suspect, is that the vendor sold them in the
wrong potting material that harbored bugs and also encouraged root rot.
The other three--from other vendors and that were in great potting
material with they arrived--are doing just peachy in the same
conditions. All were repotted about 2 months ago and are receiving the
same treatment. So sometimes it's not only your care but also the care
or potting situation that you inherited that can cause problems. My
belief is that if you don't lose the plant entirely, it should recover
with proper treatment and culture. -M

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Old 01-11-2005, 11:37 AM
Ray
 
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Default Help -- black spots & sick plant

Any chance you could post a photo on alt.binaries.pictures.orchids?

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies, Artwork, Books and Lots of Free Info!


wrote in message
ups.com...
Can someone help identify what might be wrong with my phal & what to do
about it? It's had a little black spot on the edge of one leaf for
quite a while, & there's a nick in the leaf in that spot, which is a
little bigger & along the edge now, & the spot is very hard, & black.
I've suddenly discovered that the plant has developed a lot more black
spots, over new & old leaves both. Some are down at the base of the
leaves, & a few are right in the middle of an otherwise healthy looking
leaf. However, it's starting to lose colour & the leaves are getting
some icky paler green tending to yellow; this has happened since last
watering a few days ago.
The spots are 3 or 4 mm across, uneven, hard, raised & bumpy. Looks
like some sort of... ergot-y thing, I don't know.
It's currently in bloom & has been since sometime in the summer. The
flowers are ok, except for one or 2 little spots that you might get
from water (?) or abrasion, on an older flower. The roots look fat &
healthy too. This plant is, I think, generally on the dry side because
of its location & the very loose potting mix & small clay pot, but this
month has been very dark & gloomy -- I did try to spread out the
watering more than usual, & I usually dry the leaves before I put it
back, but maybe I left it a little damp? I may have a tendency to
overfertilize but I'm working on it... In any case it looks like
whatever, has got into the plant's system now.
I have looked up my orchid books. Says sunburn can cause sunken black
spots, & rot causes soggy spots. Fungus causes "spotty leaves."
Nothing about raised black warty things.
Then I did an archive search here & read some of the 219 results that
"black spots" returned. I'm still not sure exactly what it is or what
I should do with it. This is "Dad's" plant (i.e. he picked it out &
wanted me to buy it, but I get to look after it) & he will be very,
very disappointed if it croaks. I put cinnamon on it in a panic,
sprinkling it liberally around the crown & on all of the spots that it
will stick to, although some are on the undersides of the leaves. What
else can I do? Does anyone use the garlic tea one of my books
recommends (1 crushed clove in a litre of water)?
I really don't want to lose this plant. Any ideas would be most
appreciated.
Thanks!

Alison



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Old 03-11-2005, 02:13 AM
 
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Default Help -- black spots & sick plant

Well, I'm not digital, & I live in the middle of nowhere, so it takes
forever to get pictures done. I could take one, but by the time I got
the film done, & made another trip away, & got the films processed, who
knows what state the plant would be in. I could bug one or two casual
acquaintances to ask if they have a digital camera, but not sure how
things work from there.

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Old 03-11-2005, 02:15 AM
 
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Default Help -- black spots & sick plant

I appreciate all the suggestions. No scale -- I have looked very
carefully, I do know what they look like & have had them on other
plants but not near this one, & they don't make raised black warty
spots like that. Also there are 2 other phals on the same windowsill
getting the same care, & they are quite happy, & all of them have been
for years. So I'm not sure about environmental factors either. I was
wondering if it could be some sort of infection from an injury to a
leaf.
I'll keep an eye out for the book you mentioned.

Alison

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