Shop Orchid Care OrchidTalk Orchid Forum Weather Station Links Nursery

Welcome to OrchidTalk Orchid Forums


The Friendliest Orchid Community on the Internet!


  •  » Learn to Repot your Orchids
  •  » Learn Orchid Care Tips and Secrets
  •  » Find the perfect Orchid for your Growing Environment
  •  » Chat with Orchid Growing Professionals

OrchidTalk - "Bringing People Together to Grow Orchids Better!"


Let us help you grow your Orchids better; Join our community today.


YES! I want to register an account for free right now!


Register or Login now to remove this advertisement.

Page 1 of 2 12 LastLast
Results 1 to 10 of 18
Like Tree14Likes

Cattleya problem plant..

This is a discussion on Cattleya problem plant.. within the Orchid Ailments / The Compost Pile forums, part of the Orchid Culture category; I have had this plant (division) for a little over 2 years. The culture has ...

Click here to increase the font size Click here to reduce the font size
  1. #1
    Chris in Hamilton's Avatar
    Chris in Hamilton is offline Senior Member
    My Grow Area
    Windowsill
    Favorite Orchid(s)
    Dendrobium, Cattleya
    Join Date
    Jul 2014
    Gender
    Male
    Location
    Ontario, Canada
    Posts
    4,066
    Member's Country Flag

    Default Cattleya problem plant..

    I have had this plant (division) for a little over 2 years. The culture has been about the same as my other C. alliance regarding water, light etc. with small variations regarding light. When I got it it had two new leads each about 2" long. I put it on a top shelf about 6" from fluorescent lights and about 6" from a NW window. Those growths were fine until they matured, then they developed the brown/black sunken areas. These look the same from the bottom of the leaf as the top. I thought perhaps it getting too much light and moved it away from the lights to a shelf 2' lower in the same window. Last spring 2 new leads came in but the same thing happened. Great until they matured and then kablooie(sp?). Last winter I moved it 3" from the glass at the same location. This years growth was fine 3 days ago, checked when I watered. Today I went to water and same thing. What really tick's me off is that this time it was in sheath. I am inclined to toss it (need the space for attractive plants) but if anyone knows what the Sam heck is going on here and would like to share it would be very much appreciated. The plant is C. Korat Spots. The top picture was taken in the spring. You can see the 2 new growths. The next is one of the mature leaves today.
    Attached Images Attached Images   

  2. #2
    Kauaiguy's Avatar
    Kauaiguy is offline Senior Member
    My Grow Area
    Outside 24/7
    Favorite Orchid(s)
    Cattleyas Challenging to grow
    Join Date
    Jun 2016
    Gender
    Male
    Location
    Kauai, Hawaii
    Posts
    228

    Default

    The purplish coloration of the leaf leads me to believe that it's a fungal infection such as black rot fungus, which starts out purplish in color, turns black and eventually causes soft rotted areas. If left unchecked it can spread to the rhizomes and the roots.

    My second suspicion is a virus, but I'm leaning toward my first and if you googled cattleya black rot fungus, you will see images similar to yours.

    If that is what it is, you can drench the orchid in fungicide preferably with something that has etridiazole (sp?) "Terrazole", which is kind of expensive.

    Again, this is Guess Work on my part. Waiting to hear from others. Good Luck

    I just googled it and ran into a good article by AOS, may want to read it.

  3. #3
    Chris in Hamilton's Avatar
    Chris in Hamilton is offline Senior Member
    My Grow Area
    Windowsill
    Favorite Orchid(s)
    Dendrobium, Cattleya
    Join Date
    Jul 2014
    Gender
    Male
    Location
    Ontario, Canada
    Posts
    4,066
    Member's Country Flag

    Default

    I thought maybe fungal as well but no other s have it. The black areas always appear at the same stage in growth and the pseudobulbs are very healthy. Lots of new root growth in the pot too. I was just looking at it again (my other occupation) and it has two new growths just starting. 1st year it has done that!

  4. #4
    Carolla's Avatar
    Carolla is offline Senior Member
    Real Name
    Carol
    My Grow Area
    Under Lights
    Favorite Orchid(s)
    Phals, Catts, Onc. Alliance
    Join Date
    Dec 2012
    Gender
    Female
    Location
    Eastern WA State, USA
    Posts
    1,503

    Default

    I would treat it for fungus and isolate it and see what happens. Other than that, I really don't know.

  5. #5
    Chris in Hamilton's Avatar
    Chris in Hamilton is offline Senior Member
    My Grow Area
    Windowsill
    Favorite Orchid(s)
    Dendrobium, Cattleya
    Join Date
    Jul 2014
    Gender
    Male
    Location
    Ontario, Canada
    Posts
    4,066
    Member's Country Flag

    Default

    Sorry to both of you! Forgot to say this when Kauaiguy posted. It has been treated with fungicide several times. I put it back in isolation today Carol.
    Last edited by Chris in Hamilton; June 24th, 2016 at 05:19 PM.

  6. #6
    Kauaiguy's Avatar
    Kauaiguy is offline Senior Member
    My Grow Area
    Outside 24/7
    Favorite Orchid(s)
    Cattleyas Challenging to grow
    Join Date
    Jun 2016
    Gender
    Male
    Location
    Kauai, Hawaii
    Posts
    228

    Default

    LOL! So there you be ! Could be the reason you didn't lose the darn thing!

    Your care and diligence seems to be paying off! Pat yerself in the back bra .. as they say in Hawaii!

  7. #7
    Chris in Hamilton's Avatar
    Chris in Hamilton is offline Senior Member
    My Grow Area
    Windowsill
    Favorite Orchid(s)
    Dendrobium, Cattleya
    Join Date
    Jul 2014
    Gender
    Male
    Location
    Ontario, Canada
    Posts
    4,066
    Member's Country Flag

    Default

    Hope I'm not being rude by giving this a bump myself!

  8. #8
    Catt Mandu's Avatar
    Catt Mandu is offline Senior Member
    My Grow Area
    Porch/Patio.
    Favorite Orchid(s)
    Cattleyas, Phalaenopsis
    Join Date
    Jun 2012
    Gender
    Male
    Posts
    208

    Default

    Does not appear to be viral.

    Either fungal or bacterial. Black rot is a possibility. If the black seems to be spreading, cut off the parts of the leaf that are discolored nearby.

    No one fungicide will treat all fungi. Look up the St. Augustine Orchid Society, there is a lot of good information on fungal and bacterial diseases and treatments available. As a long-term preventative, incorporate calcium into your nutritional program.
    Posted via Mobile Device

  9. #9
    Chris in Hamilton's Avatar
    Chris in Hamilton is offline Senior Member
    My Grow Area
    Windowsill
    Favorite Orchid(s)
    Dendrobium, Cattleya
    Join Date
    Jul 2014
    Gender
    Male
    Location
    Ontario, Canada
    Posts
    4,066
    Member's Country Flag

    Default

    It is really frustrating. I was already getting long winded in my original post so cut it short. Trying to remember everything but more info. I treat my orchids for fungi twice yearly. Once with copper sulfate in February and one of those green products that I can't remember the name of in October. I've also been giving this one extra treatments. As I said none of my other plants are showing any sign of this problem. About 140 of those are Cattleya alliance. You should be able to see the pseudobulbs where I have been cutting off leaves for the past couple of years. I will include calcium in its diet. In a couple of weeks all the leaves should be black but the new growths, roots and old bulbs will be healthy and I'll post another pick. St Augustine site has been in my favourites for a couple of years

  10. #10
    Kauaiguy's Avatar
    Kauaiguy is offline Senior Member
    My Grow Area
    Outside 24/7
    Favorite Orchid(s)
    Cattleyas Challenging to grow
    Join Date
    Jun 2016
    Gender
    Male
    Location
    Kauai, Hawaii
    Posts
    228

    Default

    Copper Fungicides may slow down the spread of Black Rot but I don't think it's the answer to eradicating the problem.

    I think that you'll have to go with something containing the chemical I mentioned above (etridiazole) or as mention in one of the St Augustine articles, the author uses something called: Subdue. Both are very expensive, so you'll have to weigh the cost of the chemicals vs the cost of the orchid.

    I guess it will have to come down to: 1) How much you like this orchid? 2) Is it spreading to the others? 3) Is it replaceable?

    The unknown answer of course is: Will it work? Hard to justify the cost if the results is minimal. At that point I would stay with the copper fungicide since it seems to slow it down some. I've also read somewhere that cinamon is being used to control the fungus. JMO

Page 1 of 2 12 LastLast

Similar Threads

  1. Problem orchid plant: Rk. Regal Red 'Paradise'
    By Birdwoman in forum Genus Specific
    Replies: 5
    Last Post: March 20th, 2013, 12:24 PM
  2. Cattleya problem
    By raindeepak4u in forum Orchid Ailments / The Compost Pile
    Replies: 2
    Last Post: April 4th, 2010, 08:21 PM
  3. problem with another cattleya
    By lora in forum Cattleyas, Vandas, Dendrobiums IN BLOOM
    Replies: 6
    Last Post: February 12th, 2010, 04:48 PM
  4. cattleya problem
    By Joan in forum General Orchid Culture
    Replies: 6
    Last Post: January 1st, 2008, 01:13 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
OrchidTalk --An Orchid Growers Discussion Forum brought to you by River Valley Orchidworks. A World Community where orchid beginners and experts talk about orchids and share tips on their care, cultivation, and propagation.