Phalaenopsis: Roots Turned Black after Repotting

[Chitmacha]

While I have many species of orchid that I care for successfully, the phalaenopsis gives me the most trouble when trying to re-pot it.

I am posting pictures of the perfectly healthy roots, which have now turned black, after being mounted; final pic. Although, the leaves still appear healthy for now. But, if I follow past plant behavior, this will slowly changes.

Does anyone have suggestions as to what I'm doing to cause this. (I get the same result whether or not I mount or pot.)

Thanks.

[RosieC]

It gives me the impression that the roots are burned in some way.

I'm thinking some sort of chemical burn rather than heat. If it was happening during usual growing I would think it could be too strong fertiliser or something, but if it's only happening when re-potting/mounting that seems less likely.

In the first pic I wondered in the dust on the roots was cinnomon. Too much cinnamon can dry out the roots too much. Really you only want the odd dab on wounds for the roots. I avoid cinnomon on roots and prefer listerine.

What do you do when you re-pot/mount. Specifically do you use anything on the roots you would not usually use on the plants when not re-potting them (such as cinnomon, listerine, other chemical or substance)?

I could be completely on the wrong track though.

[Undergrounder]

First of all the old roots don't really look in fantastic condition, even though they were green they don't have growing tips and would likely not respond well to repotting anyway. I would expect them to slowly die off, you really need to get some new root growth going.

Also the sphagnum moss quality looks pretty poor, is it old? That definitely wouldn't help. Get some fresh, springy, yellow stuff if you can..

And when you mount it, you want to be sure to cover the base of the crown with moss more than anywhere else.. it protects new roots emerging and it keeps the root system moist for longer. You've kind of done it backwards.. the way you have it will let the roots dry out and get burnt.

If you can spark it to life with better light, plenty of water and maybe a little Superthrive or KLN then the new roots will be a lot more resistant to repotting.

[King_of_orchid_growing:)]

First of all, I think the roots of the Phal in question that you believe were "healthy", were in fact just okay and reasonably alive.

I think Undergrounder made a good point about the roots not having the green root tips.

The roots you thought were "healthy" had a larger potential to die off than grow new tips.

I could tell you right now, the ones that were yellowish were not "healthy" roots. If I had to probe your experience of which roots died first, I believe the ones that were yellow were the very first ones to bite the dust. Leaving you with the green roots with no new growing tips.

And when you had issues trying to keep those alive, those "healthy" green roots started to croak one by one. Until you were left with a sad bundle of stubby fungus laden roots.

How close am I to the truth here?

Look don't feel bad, I've been there too. So has a lot of other people.

Secondly, why is there cinnamon all over the place?

Cinnamon can dry up the root cells very easily. The chemical compounds in cinnamon also acts as a growth inhibitor.

I advise you to be careful with how much contact the roots have with cinnamon.

Don't feel bad about this one as well, I made the same mistake but worse. I learn quick though. Large amounts of cinnamon all over an orchid is not good.

Third, Undergrounder has a good point about the moss. It looks pretty old and nasty. Good fresh moss is a yellow-buff color and fluffy.

Did you just re-use the moss that came in the pot when you first bought the orchid?

I know money may be tight, but in the end getting fresh new potting material will save you big $$$ in the long run.

How much moss did you use when mounting?

You're in the South. The climate is very similar to that of where Phals naturally encounter.

If you're mounting them, you should really pay close attention to pics of them growing in the wild and note that there is only a thin layer of moss if any on the trees they're growing on.

If there's any consolation, I just only within the past couple years found out about the pics of Phals growing in the wild.

Fourth, you didn't mention air circulation. Fungus on the roots don't look like the plant was grown in an area with good air circulation to prevent that kind of heavy fungus growth.

Fifth, I think RosieC may have something with over fertilizing and burning the roots as well.

At any rate, I think that the black roots may still be nominally alive.

Get fresh moss, and put a thin layer of moss that is only one strand thick on the mount first. Then put the Phal on top and work the moss around the roots. Like Undergrounder said, cover the roots closer to the leaves a bit more, but still leave some open patches available.

Water regularly and you should be fine.

[King_of_orchid_growing:)]

I just thought of this.

Many orchids are sensitive to chlorine btw.

If your water is high in chlorine content, I would advise against using tap water.

Or if you don't have access to distilled or RO/DI water, sit the tap water in a container for 24 hours and the chlorine will dissipate. Then use.

Chlorine is a bleaching agent if you didn't know.

The active ingredient in household bleach is actually the chlorine.

[camille1585]

Actually King, I think that those yellow roots were perfectly healthy. If they were in the center of the pot they weren't getting light, so no chloroplast production, so no green color. Other than that, I pretty much agree with all that has been mentioned so far.

[RosieC]

I think Camille is right. I've had ones that colour come from the center of the pot.

What is more concerning is that there are no new tips on any of the roots, but then I have seen those develop again later.

[Undergrounder]

Originally Posted by RosieC

What is more concerning is that there are no new tips on any of the roots, but then I have seen those develop again later.

Yeah.. keep it well watered, well lit, warm and humid if possible and you might still be able to get some branches coming out of existing roots.

Good luck!

[King_of_orchid_growing:)]

My reasoning for the yellow roots were that they appear to be waterlogged or they were old roots going out.

I've grown plants where the roots were that color and they never came around.

This was particularly true of Phal lowii. Where the roots were fully exposed to light and they were mounted as well. This was somewhat of a frustrating Phal to grow. I believe it slowly pined away due to not observing the period of dormancy and therefore overwatering the roots. I've resorted to cloning this plant and have finally succeeded in getting a nice big 1/2" callus!

Anywhoo...

Yeah, yellow roots can come from the center of the pot where the seller had a bunch of moss compacted in there. This prevent the roots from receiving the air they need to breathe. And it gets them waterlogged too.

But if you guys say those yellow roots were cool, then there might be another part of the story to this as well. It's always a possibility. So I don't doubt you guys are correct as well.

Oh, yeah, I forgot...

This is according to what I've seen in my plants, so...I'll let others be the judge on this one...

The roots that I've observed that had the low chloroplast count due to low exposure to light were not that kind of yellow. The ones I've seen that were low in chloroplasts had poorly developed velamin, the main portion of the roots were a pale white with a low level of translucency, and the tips were fully translucent with a bright yellow tip. There might occasionally be a tinge of yellow, but not like the ones I'm seeing in the first pic Chitmacha posted.