Phal. fuscata no roots & very dehydrated. Cut flower spike?

[LornaB]

Hello everyone,

This is a first time post for me so apologies if I get anything wrong! I'm quite new to the hobby. I've grown flower shop bought hybrid Phals, a Dendrobium and an Oncidium for about 5 years with no major trouble. But at the beginning of this year I found about the wonderful diversity of orchids you can grow indoors and my collection has exploded haha.

I've been really getting into Phalaenipsis species and a few weeks back I purchased a Phal. fuscata. The medium was a mix of grit and bark. The bark looked so degraded, it was black and the orchid was suffering from root rot. Apparently it was grown in very wet conditions so I'd hoped that transfering it into damp leca would suit it once I'd cleaned it up and removed all the dead roots. Sadly the few roots it had left died and it's looking very dehydrated now. All my other species Phals loved semihydro (once they adapted) and grew loads of roots but they were in better condition to start with.

I've read that I'm best trying to keep it in humid (but ventilated) conditions to encourage new root growth and keep it hydrated. I think I'll use some spare sphagnum moss I have and keep it in a cup to increase humidity. I've now cut away all the dead roots, sprayed the base with hydrogen peroxide 3% and dried it off.

However it does have a very healthy looking flower spike. Everyone always seems to say to never cut sequential blooming flower spikes. But I'm really worried that it might die if I don't. I'd love to know what you guys think. Would that be the best thing for me to do?

Thanks in advance!

Lorna B

[Roberta]

I would not cut the flower spike. If the plant needs to, it can absorb nutrients from the spike (then the spike would wither) but if that is not happening, you won't improve the plant by cutting the spike, you would be instead removing the plant's reserves. Once it grows roots, it will be fine.

[estación seca]

I agree. If it had flowers I would advise cutting them off; they lose a lot of water. Stressed Phals often stop developing flowers on spikes when conditions are bad.

I suggest not spraying roots of any orchid with hydrogen peroxide. It damages delicate tissue. I only use peroxide for Phals with crown rot. I drip a few drops just into the crown.

It's not a good idea to spray plants to prevent diseases. This selects for more resistant and virulent organisms. Root rot on Phals is seldpm caused by microorganisms. It is caused by drowned roots. Use specific fungicides or antibiotics only if you know which organism you have, and know it is susceptible to the chemical you have. Not all fungi are susceptible to every fungicide.

Plants have an amazing ability to fight off infections, as do mammals. Most diseases jn hobbyist collections are due tp poor growing conditions stressing the plants, which permits attack.

[Roberta]

Another thing about that flower spike... it likely won't produce flowers while the plant is struggling... On those successive bloomers, a spike can sit for a very long time, then when the plant is happy, pop out a flower. In the meantime, it is green and hydrated which are both good.

[LornaB]

Thanks guys,

That makes sense about the spike being a source of nutrients. Hopefully that means it's not quite as bad as I'd thought! Just got a bit worried since the leaves look so dehydrated but it's heartening to hear it could still bounce back

I'll leave the spike alone and just try to focus on keeping the orchid as hydrated as possible, hopefully my method will work. Fingers crossed it pulls through! On the stem it had previously tried to grow new roots but they had rotted away before I got it. Hopefully it can grow more soon.

Thanks also about the mention of Hydrogen peroxide. It was recommended to me as an alternative to more harmful chemicals but if that's still too strong (and contributes to making stronger pathogens) then I'll avoid using it unessesarily. Thanks for the tip!

[LornaB]

Sadly no amount of humidity was enough to save it

It slowly turned yellow and all the leaves fell off.

Now wishing that I had cut the flower spike as that's the only thing that's still green. The spike even decided to bud despite it's poor health. I think that may have been the final straw

I really wish it had made a keiki instead so at least I could have the plant still. No idea why it decided trying to bloom was a good idea. If there's any suggestions to save it I'd like to try but I suspect it's a goner

Thanks anyway guys. Hopefully I can find a healthier plant next time.

All the best,

Lorna

[Roberta]

Cutting the flower spike would not have saved it. A dying plant may spike to try to reproduce itself before it goes. Usually not successful because any flowers are going to be weak. When the roots are gone, the plant has no way to absorb moisture. With good roots, even if the leaves are gone, a basal keiki is possible. Otherwise, the odds are against you. It is much easier to keep a healthy plant healthy than to try to cure one that was distressed before you got it. So yes, get a healthy plant, far more rewarding and less frustrating. Probably, cross the vendor from whom you purchased it off your list. There is no excuse for someone to sell a plant in such poor condition.

[King_of_orchid_growing:)]

In the future, I'd recommend to forego the hydrogen peroxide treatment. Hydrogen peroxide does a significant amount of damage to cellular membranes while it is active.

There are 3 ways to render hydrogen peroxide inactive:

1. Exposure to air.

2. When it comes into contact with an enzyme called catalase that quickly breaks it down.

3. Neutralize it with an alkali, (something that has a pH above 7.0). Note: Hydrogen peroxide is an acid.

When hydrogen peroxide is active, it steals oxygen atoms from the phospholipid molecule that makes up the phospholipid bilayer of a cell membrane. This causes a chain reaction that continues even after the hydrogen peroxide is no longer active until it is stopped by an antioxidant. Despite cells being able to create catalase to stop the activity of hydrogen peroxide, it does not stop the oxidation process happening to the cell membrane's phospholipid bilayer. Hydrogen peroxide damages the structural stability of the cellular membrane in this way. An antioxidant is the thing that stops the chain reaction of oxidation happening to the phospholipid bilayer.

There's a reason why the edges of your fingernails get raw when exposed to a significant amount of 3% hydrogen peroxide. What I mentioned in the previous paragraph is the reason why.

When you used hydrogen peroxide, it caused further stress on the plant. Oxidative stress is not easy to visually observe, but the damage is still done regardless of whether you were aware of it at the time or not.

Plus, I'm in the camp of removing the spike when the Phal is in distress. Removing the spike works really well to conserve energy for the plant on some epiphytic orchids, (this tactic doesn't work so well when used on the terrestrial orchids that form root tuberoids). The amount of sugar/energy production that the flower spike contributes compared to what the plant's leaves or roots produce is not that significant, relatively speaking. How do I know? You've gotta think in terms of surface area. The parts of a Phal that has the highest amount of surface area to facilitate significant amounts of sugar production via photosynthesis are the leaves, then the roots, then the stem, and lastly, the inflorescence - and for the most part, it is usually in that order, (although, in some cases, the surface area of the stem might be smaller than that of the plant's inflorescence).

If you're wondering why I listed a Phal's roots as having greater surface area compared to the plant's stem, it's because even though each individual root is narrower than the plant's stem, there are several roots that grow out of the plant and each root can potentially grow quite long. When you see how much surface area the root mass takes up, by comparison to its stem, it is much more than the surface area of the stem.

There could also possibly be physiological limiting factors that may play into why the inflorescence is not the best source of energy production for the plant, but I'm not sure what that may be at the moment.

I've also learned from experience and observation that an orchid most likely expends a lot of energy into flower production. I learned about this through learning how to grow orchids that form root tuberoids. There's a reason why orchids that form root tuberoids do not have the original root tuberoid that the stem and leaves grew out of persist after the plant has flowered. It's most likely because the energy that was stored in that tuberoid has been spent on producing leaves, a stem, and flowers. The time when the fastest deterioration of the mother root tuberoid occurs appears to be right after flower production. I've observed that the energy produced by the leaves growing out of the mother tuberoid appear to be stored in the new daughter tuberoids, not the mother tuberoid. Flowers are usually produced after the plant has not only gathered enough energy through photosynthesis, but also when it starts tapping into the reserves of energy stored in the mother root tuberoid. From the lessons I've learned from understanding the life cycle of a terrestrial orchid that forms root tuberoids, I have deduced that flower production is most likely energy costly for an orchid in general. This appears to be the case if the flowers are large.

[LornaB]

Thanks both. If I come across this orchid again from another vendor I will definitely try and get one. I'll also avoid using the Hydrogen peroxide in future.

I'm tempted to try flower stem propagation as a last ditch attempt to try and save it. Though I think I would struggle keeping it completely sterile and it's something I've never done before. But it might be a better bet than just leaving it to slowly die? Probably being stubborn now but I'd like to try at least!

Let me know what you think. Is it worth a shot? The plant does have a small section of aerial root left which still turns green when wet. So I'm not sure whether to try it or not. It's likely a goner but at least I'll have tried everything possible.

Thanks again!

[estación seca]

I would keep trying. As long as a healthy root is attached to the spike it may produce a plantlet from one of the nodes.