Purchased in Jan., 2023. Last two older growths did the same thing. Couple it just be it needs repotting? 
Any ideas as to what this is?
- Thread starter southernbelle
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Can anyone help with this?
Nothing good.
I’ve cut it off and repotted. Will douse with fungicide and bactericide.
No need for fungicide or bactericide. That's clearly a nutrient deficiency. If the old growths die quickly one after the other, leaf by leaf, it is most likely a nitrogen deficiency... It could come from the root system. However, repot, lime on top, water with an urea fertilizer and it will green up within a month or two max.
My orchids that are watered more often than once a week as small Paphs are, get 1/4 teas per gallon of MSU every watering if in bark. In moss they get flushed about every 3rd watering as I notice a buildup of salts on surface. Hard to believe they are not getting enough nitrogen.
Use a high urea nitrogen fertilizer, like a 20-20-20, then the leaves will green up very quickly. Nitrate nitrogen is not efficient at all fo Paphs, especially complexes, that are heavy feeders.
Hadley Cash at Marriott used MSU and we all know his reputation with beautiful Paphs. I’ve never had a problem with any other plant like this. Here is the make up of my fert. Everyone I’ve ever heard speak says not to use urea nitrogen fertilizers on orchids, so your saying to, is confusing. It won’t green up a leaf that’s already had tissues die.
The Urea Wars. There are certainly lots of different opinions.
My Papsh, Phrags, Zygos, Odonts, Disas and Cymbidiums accelerated their growth and flowering when I started incorporating urea into the formula. General vitality, as measured strictly by observation, is way up as well.
I now feed with 50% of the N as urea. I would use a higher percentage but our water chemistry disallows without a second fertilizer injector system. Constant feed, great results. No leaf burning, no salt accumulation. I've seen this sort of discoloration of leaves in the past and no longer do now that I'm on the urea bandwagon.
My Papsh, Phrags, Zygos, Odonts, Disas and Cymbidiums accelerated their growth and flowering when I started incorporating urea into the formula. General vitality, as measured strictly by observation, is way up as well.
I now feed with 50% of the N as urea. I would use a higher percentage but our water chemistry disallows without a second fertilizer injector system. Constant feed, great results. No leaf burning, no salt accumulation. I've seen this sort of discoloration of leaves in the past and no longer do now that I'm on the urea bandwagon.
This looks very similar to what I’ve seen on a few of my plants this summer. Where I had small spots a couple of direct applications of Physan 20 (Full strength) with a cotton pad stopped it. For larger areas I cut it off and treated the plant (watered and sprayed with diluted Physan. Unfortunately it was in the crown of Philip’s Lady and I lost the plant.
I think you did the right thing. Fingers crossed that your plant will be alright.
I think you did the right thing. Fingers crossed that your plant will be alright.
Yep, unfortunately treatment with fungicide 3 weeks with different ones after each treatment in a bag for 24 hours. Of course minimum water and no fertiliser.
That's a nitrogen deficiency as a certain fact. MSU is a nitrate nitrogen fertilizer, and it is not suitable for many orchids to get really glossy dark green leaves. Complex paphs are even more sensitive to that, and one of the key symptoms will be the loss of the leaves progressively, with markings and pitting, until only a tiny plant remains. As it is tiny, it will grow up again from the little nitrogen that is supplied, take a couple years to mature a new plant, bloom, go down to 1 tiny growth after 1-2 years, etc...
I do grow clumps of complex some of them were over 20-30 growths, from a 2-3 growth plant, within 2 years, so I have experience with these... There are pictures of them on my Facebook.
No fungicides/bactericides needed, repot eventually as the pot is quite small for a plant this size, and a 20-20-20 or 30-10-10 fertilizer with urea will fix the problem, including greening the old leaves, within a month. The most important at that stage is to feed the plant properly.
Justin posted a similar problem on his rothschildianum before, that he solved too by the constant use of an urea based, 20-20-20 fertilizer. The feeding schedule of Hadley Cash had as well urea based fertilizers on a periodic schedule, and from what I know he was using the MSU Well water version on top, which has a lot of ammonium compared to the RO water, which contains only nitrate. As for me, I grow a few plants of Paphs here and there.
I do grow clumps of complex some of them were over 20-30 growths, from a 2-3 growth plant, within 2 years, so I have experience with these... There are pictures of them on my Facebook.
No fungicides/bactericides needed, repot eventually as the pot is quite small for a plant this size, and a 20-20-20 or 30-10-10 fertilizer with urea will fix the problem, including greening the old leaves, within a month. The most important at that stage is to feed the plant properly.
Justin posted a similar problem on his rothschildianum before, that he solved too by the constant use of an urea based, 20-20-20 fertilizer. The feeding schedule of Hadley Cash had as well urea based fertilizers on a periodic schedule, and from what I know he was using the MSU Well water version on top, which has a lot of ammonium compared to the RO water, which contains only nitrate. As for me, I grow a few plants of Paphs here and there.
This is one of the issues with discussions about feeding - most “answers” are based upon anecdotal evidence, and there may be other factors involved that are not identified. Yeah, the symptoms might very well be a nitrogen deficiency, but isn’t it possible that another part of Souther Belle’s culture is leading to that?
I have been using MSU RO and then K-Lite for over 20 years. They have the same nitrate;ammonium ratio. I have never seen such symptoms, including back when I grew a very wide variety of plants.
I am absolutely not denying the potential benefit of urea. It is well known that it leads to rapid “greening up” in plants, but some of that comes from the fact that it is better for foliar application than are nitrates and ammoniums.
I know an excellent grower of paphs that regularly adds it to his feeding regimen, and he claims benefits. But then again, I have read postings about an excellent grower who primarily feeds his award-winning paphs nothing but calcium nitrate.
I have been using MSU RO and then K-Lite for over 20 years. They have the same nitrate;ammonium ratio. I have never seen such symptoms, including back when I grew a very wide variety of plants.
I am absolutely not denying the potential benefit of urea. It is well known that it leads to rapid “greening up” in plants, but some of that comes from the fact that it is better for foliar application than are nitrates and ammoniums.
I know an excellent grower of paphs that regularly adds it to his feeding regimen, and he claims benefits. But then again, I have read postings about an excellent grower who primarily feeds his award-winning paphs nothing but calcium nitrate.
Here is an example of what incorporating urea into our program has achieved. Paph. Dollgoldi grew very slowly if at all for me before urea, as did all of the multifloral primaries. This summer it put on two leaves, three new growths and is wanting to flower. Great foliage color as well. Nitrate N was just not cutting it. Yes, the tag is misspelled.
And if the urea wars aren't enough, we have the pH wars concerning both the solutions we use and what prevails at the root zone. That brings in differences in potting media and water sources. This multivariable equation is impossible for me to solve. I decided to hedge on everything and am using a rotation of 6 different solutions with pH optimized for either the roots or for foliar feeding of urea. It isn't that difficult to do. I think it is working, but learning about significant changes like this will take at least a year.
As an experiment, I am having a batch of modified K-Lite blended that will incorporate 15% NH4-N; the original and MSU RO have 5%, while MSU WW is 25%. I thought about going higher, but that pushes it to be "K-Even-Lite-r"
Terry is dead-on with the multivariate nature of this discussion. Evaluating the switching of raw materials is not a univariate thing unless the nitrogen loading, watering regimen, and growing conditions are all identical. Plus (sorry, kman), one plant does not produce conclusive results and as we know, larger plants grow faster than do smaller ones, so the results, while encouraging, really don't tell us much.
Terry is dead-on with the multivariate nature of this discussion. Evaluating the switching of raw materials is not a univariate thing unless the nitrogen loading, watering regimen, and growing conditions are all identical. Plus (sorry, kman), one plant does not produce conclusive results and as we know, larger plants grow faster than do smaller ones, so the results, while encouraging, really don't tell us much.
tnyr5
Well-Known Member
Let's look at the problem from a purely economic perspective:
If Xavier is right, it's a ten-dollar fix. If he's not, you've done nothing but feed your plants.
Compare that to potentially spending multiple hundreds of dollars on fungicides and I know which one I'd try first.
If Xavier is right, it's a ten-dollar fix. If he's not, you've done nothing but feed your plants.
Compare that to potentially spending multiple hundreds of dollars on fungicides and I know which one I'd try first.
No problem, Ray. You are absolutely right. I have several batches of seedlings growing now at various stages: Phrags, Paphs, Odonts and Cymbidiums. All have shown faster - if not much faster - growth once urea was incorporated into my fertilizer formula. Phrags of all sizes have shown the most dramatic improvement, but the effect has shown all across the board regardless of plant age.
I've grown Cymbidiums since 1959, and thought I had their culture wired. But as I started to up the percentage of urea in the constant feed I use for all genera, the leave took on a bright glossy green and the growth accelerated. I've had to repot some out of season as the roots have pushed the plants out of the pots. Never seen this before. You can teach an old dog new tricks.
There are so many factors, but to my eye it was the introduction of urea that has made a remarkable difference. My practices are different from the norm in many ways, including constant feed at a high level and frequent watering. But this is the one thing that has without a doubt made a big difference for me.
Okay I’m going to be the big dummy that asks this question. If urea is actually good for orchids then why has it been touted as bad for them for so long?
Here is what Claud AI says when answering this question:
This is an interesting question about a somewhat controversial topic in orchid care. To address it, I'll break down a few key points:
1. Historical perspective:
Urea has been traditionally viewed as harmful to orchids, primarily due to concerns about its potential to burn roots and leaves if applied incorrectly. This cautionary stance has been widespread in orchid growing communities for many years.
2. Scientific understanding:
Urea is a form of nitrogen that plants, including orchids, can use. However, it needs to be broken down by soil microorganisms into forms more readily absorbed by plants (ammonium and nitrate). Orchids, especially epiphytic ones, often grow in environments with limited microorganism activity, which may have contributed to the belief that urea is not suitable for them.
3. Recent research:
More recent studies and experiences of some growers suggest that urea can be beneficial for orchids when used correctly. It can provide a slow-release source of nitrogen, which is essential for plant growth.
4. Reasons for the shift in perception:
- Better understanding of orchid nutrition
- Improved fertilizer formulations
- More controlled application methods
- Recognition that different orchid species may have varying tolerances
5. Ongoing debate:
The use of urea for orchids is still debated. Some growers prefer other nitrogen sources, while others have found success with urea-containing fertilizers.
The long-standing belief that urea is bad for orchids likely persisted due to:
- Cautionary approach in orchid care
- Potential for misuse leading to plant damage
- Slow adoption of new information in hobbyist communities
- Varied results depending on orchid species and growing conditions
It's important to note that if urea is used for orchids, it should be in appropriate concentrations and as part of a balanced fertilizer regimen. The shift in perception is gradual, and many growers still prefer to err on the side of caution.
Expanding on the second point, it says:
I'd be happy to elaborate on point #2 regarding the scientific understanding of urea and its relationship to orchids.
Urea and plant nutrition:
1. Chemical composition:
Urea (CO(NH₂)₂) is an organic compound containing 46% nitrogen, which is a higher concentration than many other nitrogen sources used in fertilizers.
2. Nitrogen conversion process:
For plants to use the nitrogen in urea, it must undergo a two-step process:
a) Hydrolysis: Urea is broken down into ammonia (NH₃) and carbon dioxide (CO₂) by the enzyme urease.
b) Nitrification: Ammonia is further converted to nitrite (NO₂⁻) and then to nitrate (NO₃⁻) by soil bacteria.
3. Microorganism dependence:
This conversion process heavily relies on soil microorganisms, particularly bacteria. The efficiency of this process can vary depending on environmental conditions like temperature, moisture, and pH.
4. Orchid growing environments:
Many orchids, especially epiphytic species, naturally grow attached to trees or rocks rather than in soil. These environments typically have:
- Limited microbial activity compared to soil
- Rapid drainage and limited water retention
- Exposure to air movement
5. Challenges for urea use in orchid media:
- Less microbial activity can slow down urea conversion
- Faster drainage may wash away urea before it's fully converted
- Risk of ammonia buildup if conversion is incomplete, which can be toxic to plants
6. Adaptation considerations:
While orchids can adapt to use urea, they may not have the same efficient mechanisms for urea uptake and conversion as plants that typically grow in microbe-rich soil environments.
7. pH effects:
The conversion of urea can temporarily raise substrate pH, which might affect nutrient availability for orchids, many of which prefer slightly acidic conditions.
This scientific understanding helps explain why urea has been viewed cautiously for orchid use. However, it's worth noting that with proper application methods and in appropriate growing conditions, these challenges can be mitigated, which is why some growers have found success using urea-containing fertilizers for orchids.
AI is what it is, but this makes general sense to me.
This is an interesting question about a somewhat controversial topic in orchid care. To address it, I'll break down a few key points:
1. Historical perspective:
Urea has been traditionally viewed as harmful to orchids, primarily due to concerns about its potential to burn roots and leaves if applied incorrectly. This cautionary stance has been widespread in orchid growing communities for many years.
2. Scientific understanding:
Urea is a form of nitrogen that plants, including orchids, can use. However, it needs to be broken down by soil microorganisms into forms more readily absorbed by plants (ammonium and nitrate). Orchids, especially epiphytic ones, often grow in environments with limited microorganism activity, which may have contributed to the belief that urea is not suitable for them.
3. Recent research:
More recent studies and experiences of some growers suggest that urea can be beneficial for orchids when used correctly. It can provide a slow-release source of nitrogen, which is essential for plant growth.
4. Reasons for the shift in perception:
- Better understanding of orchid nutrition
- Improved fertilizer formulations
- More controlled application methods
- Recognition that different orchid species may have varying tolerances
5. Ongoing debate:
The use of urea for orchids is still debated. Some growers prefer other nitrogen sources, while others have found success with urea-containing fertilizers.
The long-standing belief that urea is bad for orchids likely persisted due to:
- Cautionary approach in orchid care
- Potential for misuse leading to plant damage
- Slow adoption of new information in hobbyist communities
- Varied results depending on orchid species and growing conditions
It's important to note that if urea is used for orchids, it should be in appropriate concentrations and as part of a balanced fertilizer regimen. The shift in perception is gradual, and many growers still prefer to err on the side of caution.
Expanding on the second point, it says:
I'd be happy to elaborate on point #2 regarding the scientific understanding of urea and its relationship to orchids.
Urea and plant nutrition:
1. Chemical composition:
Urea (CO(NH₂)₂) is an organic compound containing 46% nitrogen, which is a higher concentration than many other nitrogen sources used in fertilizers.
2. Nitrogen conversion process:
For plants to use the nitrogen in urea, it must undergo a two-step process:
a) Hydrolysis: Urea is broken down into ammonia (NH₃) and carbon dioxide (CO₂) by the enzyme urease.
b) Nitrification: Ammonia is further converted to nitrite (NO₂⁻) and then to nitrate (NO₃⁻) by soil bacteria.
3. Microorganism dependence:
This conversion process heavily relies on soil microorganisms, particularly bacteria. The efficiency of this process can vary depending on environmental conditions like temperature, moisture, and pH.
4. Orchid growing environments:
Many orchids, especially epiphytic species, naturally grow attached to trees or rocks rather than in soil. These environments typically have:
- Limited microbial activity compared to soil
- Rapid drainage and limited water retention
- Exposure to air movement
5. Challenges for urea use in orchid media:
- Less microbial activity can slow down urea conversion
- Faster drainage may wash away urea before it's fully converted
- Risk of ammonia buildup if conversion is incomplete, which can be toxic to plants
6. Adaptation considerations:
While orchids can adapt to use urea, they may not have the same efficient mechanisms for urea uptake and conversion as plants that typically grow in microbe-rich soil environments.
7. pH effects:
The conversion of urea can temporarily raise substrate pH, which might affect nutrient availability for orchids, many of which prefer slightly acidic conditions.
This scientific understanding helps explain why urea has been viewed cautiously for orchid use. However, it's worth noting that with proper application methods and in appropriate growing conditions, these challenges can be mitigated, which is why some growers have found success using urea-containing fertilizers for orchids.
AI is what it is, but this makes general sense to me.
