Black Rot?

[monet]

Hi everyone, my orchid has what I think is black rot. I have treated it before it is looking very sad. I would like to re pot it. What pot would you use?

[Dollythehun]

Bump.

[Orchid Whisperer]

Not positive it is black rot from the photos.

Repotting now is sort of like re-arranging your furniture when the house is on fire.

Instead, I would focus on cutting off all tissue that is infected. cut into unblemished green, ahead of any color change. Use a flame-sterilized and cooled sharp blade ahead of every cut.

If you arrest whatever infection causes the yellowing, and the plant is recovering, repot in an unglazed terracotta pot, coarse medium.

[monet]

Hi Orchid whisperer, Thank you for your reply. I did sterilize the blade and used rubbing alcohol on the cuts mixed with cinnamon. I am guilty of using some of the water from another that had drained off a lesson learned. I grew this from 1 leaf and was looking forward to some flowers. My lovely secret love is in full flower the smell is fills the conservatory.

[dounoharm]

akkk! looks like too much water to me, and possibly contamination from something....I would open up that root ball, cut off everything with sterilized scissors or knife....

I would mix up some fresh physan and spray everything you are going to use on the plant, including the plant itself....as, I said before, open up the root ball.....in pot bound cases like this, I just cut in 3 places, about an inch from the plant, straight down with my knife. worry those plant roots loose and see whats in the middle.....you might have an unseen problem inside there.....get all the cut and dead roots out and loosen up the rhizomes so you can see it all....cut the damaged portions out.

then, just lay the dissected plant on some newspaper to dry out some....rot is wet, right?....spray every couple days with that physan you mixed up....
do NOT leave it in strong light while it is 'healing'...put it in a shady spot....

after about a week, you can see if it is spreading or not....if it is, just keep cutting till you finally get to the end....orchids can take months out of a pot!

when it starts new growth, and that is clean of rot, just place it in a clay pot, no medium for a couple more weeks....

its a long process, but you should be able to rejuvenate it.....but recall how it got to be that way and adjust your watering....maybe less often? and with fresh water....

cattleyas really like to dry out between waterings, and when you have such a tight root ball, it is probably still wet in the middle when the outer roots look dry....this is why you repot every year or two....

just my 2 cents, good luck!

[Orchid Whisperer]

Originally Posted by dounoharm

akkk! looks like too much water to me, and possibly contamination from something....I would open up that root ball, cut off everything with sterilized scissors or knife....

I would mix up some fresh physan and spray everything you are going to use on the plant, including the plant itself....as, I said before, open up the root ball.....in pot bound cases like this, I just cut in 3 places, about an inch from the plant, straight down with my knife. worry those plant roots loose and see whats in the middle.....you might have an unseen problem inside there.....get all the cut and dead roots out and loosen up the rhizomes so you can see it all....cut the damaged portions out.

then, just lay the dissected plant on some newspaper to dry out some....rot is wet, right?....spray every couple days with that physan you mixed up....
do NOT leave it in strong light while it is 'healing'...put it in a shady spot....

after about a week, you can see if it is spreading or not....if it is, just keep cutting till you finally get to the end....orchids can take months out of a pot!

when it starts new growth, and that is clean of rot, just place it in a clay pot, no medium for a couple more weeks....

its a long process, but you should be able to rejuvenate it.....but recall how it got to be that way and adjust your watering....maybe less often? and with fresh water....

cattleyas really like to dry out between waterings, and when you have such a tight root ball, it is probably still wet in the middle when the outer roots look dry....this is why you repot every year or two....

just my 2 cents, good luck!

Whoah Nelly!

I think that is a lot to assume from 3 photos.

It might be a good idea to reduce watering for a bit until whatever infection is under control, but it is not looking dehydrated. Why chop all the roots off?

I stick to my recommendation (35 years growing Cattleyas)

[Optimist]

To me, that mottling looks like it is in a somewhat higher intensity light than it can physically take. Yellow leaves can also mean that. A good orchid color is about pea-green. Maybe pear-green.

[dounoharm]

Whoah Nelly!

I think that is a lot to assume from 3 photos.

It might be a good idea to reduce watering for a bit until whatever infection is under control, but it is not looking dehydrated. Why chop all the roots off?

I stick to my recommendation (35 years growing Cattleyas)

lol, isn't it great? all sorts of ideas popping out....(only 35 years? I can trump that with a degree in horticulture....) I do like to fix things....dig in to find the root of the problem without fiddle-faddle....but, as I said, just my 2 cents worth...take it or leave it....

[estación seca]

Were the leaves firm, or wet and mushy? My first thought was sunburn.

And my next thought was calcium deficiency.

[Orchid Whisperer]

The more I look at the yellowing, which seems most common near leaf tips, the more I am thinking anthracnose, or a similar fungal disease. I would still consider treating with a SYSTEMIC fungicide like Cleary's (unlikely you will find it in conventional garden centers, should be available online, or if not sold in the U.K., find another systemic fungicide).

Estacion seca is right to suggest that more calcium could help. Calcium is important for disease control.