Why are my roots dying?

[Ray]

I see a whole big development of misconception here, due - I suspect - to incomplete information, so let me probe this a bit.

1. How long have the plants been in semi-hydro culture?
2. Are the dying roots the ones that were present before transferring them? If so, their death is more-or-less expected.
3. At what concentration are you mixing the Physan?
4. How often have you applied it?
5. How frequently have you been watering?
6. What is your water supply like?
7. What fertilizer are you using?
8. At what concentration?
9. What have the temperature and humidity been like?
10. What kinds of highs and lows have the plants been exposed to?

Concerning algae growth, any time you have the combination of light, water, and nutrients, you will have algae growth. By itself it is of no concern, except maybe aesthetically. It grows on the pot wall only, or maybe the top of the LECA, if your environment is moist enough, and does not penetrate the interior of the pot, where there is no light.

If it is living, it will have no odor whatsoever, and actually consumes waste products, to "clean up" the root environment. If it is stinky, then something you're doing is killing it, leaving behind a cesspool for your orchids to attempt to survive in.

Oh yeah - King-o-a-o-g - you are incorrect that S/H pot size should "just fit the roots". My experiments suggest that overpotting is not an issue, for the most part. I put all phals in pots as big as their leaf spans (if I can find big enough pots), and I have an Oncidium Sharry Baby that went from 2" pot directly into a 12" s/h pot, and it has thrived.

I think the primary issue with overpotting in organic-based media is that the drying tends to be from the periphery, leaving a soppy, central core of the medium - right in the middle of the root mass - where it can suffocate them. In a decent brand of LECA, the moisture transfer between particles is so good, and the open spaces constant, so staying airy, that it isn't an issue.

[scy]

Originally Posted by quiltergal

Can you show us the S/H pots you are using? I'm wondering if maybe the reservoir is too large, and the pot not tall enough.

OMG! I can't believe this... As I went to take the picture of the orchid pots, it just died... The entire top part of the parent plant just fell off. It's still oozing and there's this disgusting white stuff. I can see it on the phal sogo grape starting so I suppose this means I have a day to save it before that one has the same fate as the noid. I just can't believe that despite all my efforts to do what's best, I killed it in the end. Anyway, here are the photos of the containers that they are in, my dens are planted the same way so if it's wrong in any way, I should know before I kill my dens too. Is there any way I can still save the sogo grape and the keiki of the noid?

The last photo is the phal sogo grape. As you can see, there is already white fuzzy stuff. I don't know what to do anymore.

[scy]

Originally Posted by Zoi2

When you water, how many times do you fill the pot?
How fast is the water draining out of the pot?
I would also like to see a picture of your pot and plant.
Here pretty soon we'll find out what's wrong
Joann

When I water, I fill it to the top one time and pour it at a moderate rate so it flushes the bottom liquid out of the bottom. Sometimes I do it one time and sometimes twice, depending on how much time I have.

[scy]

Originally Posted by RosieC

Another thing with S/H is temperature. The evaporation from the Prime Agra or Lecca can reduce the temperatures lower than the ambient temperature. In colder weather Phal roots especially can have a problem with this (mine did over the winter and started getting black spots that remind me of yours).

With mine I started using a seedling heat mat and that seemed to help. Now with the warmer weather they are doing well without that, but I'm not sure what sorts of temps you have just now and the level of evaporation (thus the amount of cooling) may be different to mine.

We have summer temperatures now. The daytime temperatures are 80-85 F and night temps are 70 F. I have low humidity.

[scy]

Originally Posted by Ray

I see a whole big development of misconception here, due - I suspect - to incomplete information, so let me probe this a bit.

1. How long have the plants been in semi-hydro culture?
2. Are the dying roots the ones that were present before transferring them? If so, their death is more-or-less expected.
3. At what concentration are you mixing the Physan?
4. How often have you applied it?
5. How frequently have you been watering?
6. What is your water supply like?
7. What fertilizer are you using?
8. At what concentration?
9. What have the temperature and humidity been like?
10. What kinds of highs and lows have the plants been exposed to?

Concerning algae growth, any time you have the combination of light, water, and nutrients, you will have algae growth. By itself it is of no concern, except maybe aesthetically. It grows on the pot wall only, or maybe the top of the LECA, if your environment is moist enough, and does not penetrate the interior of the pot, where there is no light.

If it is living, it will have no odor whatsoever, and actually consumes waste products, to "clean up" the root environment. If it is stinky, then something you're doing is killing it, leaving behind a cesspool for your orchids to attempt to survive in.

Oh yeah - King-o-a-o-g - you are incorrect that S/H pot size should "just fit the roots". My experiments suggest that overpotting is not an issue, for the most part. I put all phals in pots as big as their leaf spans (if I can find big enough pots), and I have an Oncidium Sharry Baby that went from 2" pot directly into a 12" s/h pot, and it has thrived.

I think the primary issue with overpotting in organic-based media is that the drying tends to be from the periphery, leaving a soppy, central core of the medium - right in the middle of the root mass - where it can suffocate them. In a decent brand of LECA, the moisture transfer between particles is so good, and the open spaces constant, so staying airy, that it isn't an issue.

Thanks everyone for trying to help me diagnose what went wrong here. I really do appreciate it.
1. I first repotted into s/h on March 25 of this year. It was originally overpacked in sphag and roots were rotting so I potted in bark but roots continued to die, so I did a sphag and bag and repotted in s/h when I had nubs.
2. The dying roots are a combination of new and old roots. The old roots started to branch off and develop new nubs too, so it was even more surprising that they all died.
3. Physan dilution is as recommended on bottle: 1 tsp per gallon of water so I mixed up a smaller batch of 1/4 tsp per 1 liter of water. I also rinsed thoroughly with my hands to make sure that it was off.
4. I only applied the physan when I repotted and cut roots to kill off any infection.
5. I water when the water level is low - reaches the last row of PrimeAgra in the clear container. This comes up to 4-7 days.
6. I use tap water. I don't know what kind of water I have.
7. I use Better Gro Orchid Plus Fertilizer, Water Soluble Orchid Food, No Urea 20-14-13.
8. The concentration I use is 1/8 tsp per 1 qt of water.
9. Daytime temps: 80-85 F; Night temps: 70s. Low humidity. They were only recently put behind a sheer curtain.
10. I keep them indoors only so the outdoor weather should not have affected them too much.

Questions:
1. In the future, if I see algae, should I just leave it alone or continue to unpot, scrub it clean and repot it again?
2. What do I do about this white stuff? I'm afraid to do anything that might further damage them.
3. Should I move them away from everything else for fear of spreading?

[nenella]

Hi,
I am not an expert at SH - especially with Phals in s/h, I have the least 'success' in S/h with these. But, If that were my plant I would:

- get it out the pot.
-clean up the 'white stuff' looks like mould to me?
I would probably dunk it in something like 'Listerine' only because I don't have anything stonger...

-I would also try and get a deeper pot so that the roots do not touch the wetter part of the medium. But grow towards it...

- I would definitely give it a good soak in a rooting hormone like KLN.
-I would say you keep it too wet (in your conditions) are you spraying the top of the leca often? It looks like it's staying too damp and not drying out very quickly, therefore mould is growing & your plants are rotting?

Another thing struck me - you say you put them into s/h when you had nubbins. How long were your nubbins as you may have transfered into your new medium too early as your roots were not long enough?

You need to re-start some new root growth first as soon as you've got rid of the mould.

-you may have a problem with your water & or mix of fertilizer & water?hope an experienced person chips in here. Good luck and hope it isn't too late

[scy]

Originally Posted by nenella

Hi,
I am not an expert at SH - especially with Phals in s/h, I have the least 'success' in S/h with these. But, If that were my plant I would:

- get it out the pot.
-clean up the 'white stuff' looks like mould to me?
I would probably dunk it in something like 'Listerine' only because I don't have anything stonger...

-I would also try and get a deeper pot so that the roots do not touch the wetter part of the medium. But grow towards it...

- I would definitely give it a good soak in a rooting hormone like KLN.
-I would say you keep it too wet (in your conditions) are you spraying the top of the leca often? It looks like it's staying too damp and not drying out very quickly, therefore mould is growing & your plants are rotting?

Another thing struck me - you say you put them into s/h when you had nubbins. How long were your nubbins as you may have transfered into your new medium too early as your roots were not long enough?

You need to re-start some new root growth first as soon as you've got rid of the mould.

-you may have a problem with your water & or mix of fertilizer & water?hope an experienced person chips in here. Good luck and hope it isn't too late

Would a Physan dilution of 1/4 teaspoon per 1 qt of water be too strong to dunk it in? That's the recommended dilution on the Physan packet. When I repotted into s/h, I always put the Prime Agra a layer or two above the holes on the bottom before I placed the plant over the pot and potted it up. This way, it would not have touched the reservoir. I have low humidity here so the top layer evaporates pretty quickly. When I transferred it, it was at the first sign of nubbin and it still had its original roots so I thought that it would be enough for the time being.

Also, what do I do with the part of the crown that is exposed? Should I just dump cinnamon on it after I soak it all in Physan?

[Eyebabe]

Originally Posted by RosieC

Another thing with S/H is temperature. The evaporation from the Prime Agra or Lecca can reduce the temperatures lower than the ambient temperature. In colder weather Phal roots especially can have a problem with this (mine did over the winter and started getting black spots that remind me of yours).

With mine I started using a seedling heat mat and that seemed to help. Now with the warmer weather they are doing well without that, but I'm not sure what sorts of temps you have just now and the level of evaporation (thus the amount of cooling) may be different to mine.

This is very important with phals.
I no longer use s/h for them.
I have two remaining phals that "like" it out of about a dozen.
Even with seedling mats my plants were not warm enough to flourish

[scy]

Originally Posted by Eyebabe

This is very important with phals.
I no longer use s/h for them.
I have two remaining phals that "like" it out of about a dozen.
Even with seedling mats my plants were not warm enough to flourish

I had a thermometer (round circular one) leaning on a pot and on the seedling mat during the winter and it read 60s-70s. Would this not be warm enough in the winter? What should I have done so I can avoid making the same mistake in the future? It was originally packed in sphag, which does not do well in my environment at all - never dries out and quickly rots. I changed it to a bark mix; the phal HATED it and roots died off. I sphaged and bagged to save it and remember reading that new growth would be the perfect time to transfer it over. I also liked that it gave ample humidity, especially since my area is so lacking in it. What should I do when new acquisitions do not respond to bark mix?

[scy]

I'm not even sure how to go about cleaning off the mold. I don't know what to do about the green gooey center (3rd photo). I still have a keiki with baby leaves off the side. Normally, I would just soak everything from the leaves down in Physan solution for a few minutes, but I don't know if I can get that green center wet or not. If I leave it, I'm afraid that the mold might get to that area. Can I dunk the whole entire thing in Physan or hydrogen peroxide? If so, I'll get some hydrogen peroxide. Please advise how to proceed!