Purple leaves: Cold damage, Insect stress, too much light, magnesium or phosphorous

[isurus79]

Originally Posted by Shadeflower

I just realized I never showed the vanda at it's worst to properly compare it.

You might argue "These plants are grown in very high light and are imported directly from Brazil, hence the red leaves. That's how they look naturally."

but I prefer the leaves looking more green how they are now, including on my laelia pumila which has improved nicely too. It was only on Rainmix this started happening.

I’m not arguing. I’m pointing out how plants grow naturally. You are arguing that their natural pigment is unnatural. Your leaf color preference has no bearing on the plant’s metabolic processes.

[thefish1337]

Originally Posted by isurus79

I’m not arguing. I’m pointing out how plants grow naturally. You are arguing that their natural pigment is unnatural. Your leaf color preference has no bearing on the plant’s metabolic processes.

Couldn't agree more with this. Pretty much all of my Cattleya will always have anthocyanin pigmentation under higher light levels when the growths are fresh and new which fade to a green color as they mature. All my white flowered Cattleya, they don't color up under higher light but they may become yellow-green. I believe its is often said that alba clones cant stand as much light for these reasons.

I don't grow many Vandas- just a few Neofinetia. Only the pink colored neofinetia flower turns purple like this under my light conditions. The other two are basically albescent and do not express these pigment in the leaves under the same conditions.

Personally, I like to see pigmentation because it offers me a hint about the color intensity of the potential flower of new seedlings and it also shows me that I'm giving enough light.

[estación seca]

Pigmentation can have different triggers in different plants. It's not necessarily harmful. Vandas are known to develop purple spotting in winter if magnesium deficient. Magnesium moves slowly through plants, and it may take months of supplementation to resolve.

[Shadeflower]

Last update.

Although I have a million things to report including getting rid of the reddening to some extent I can tell I haven't been able to convince anyone.
I was watching a youtube video with someone losing some leaves on their orchids and asking why. I know why but I also know said person from Orchidboard and know they would not listen. So why even ask..?

My experiment is far from over but it's become obvious this is one of those subjects like nucear physics.

You ask 8 people on the street if they could build a nuclear reactor and al 8 would say no but that doesn't mean a nuclear reactor can't be built.

But who wants to talk about building a nuclear reactor. No you ask 8 people on the street and all they will want to talk abotu is how many cups of coffee they will be able to make from having one.

An unforseen consequence of this experiement is that growth has dramatically increased. But pseudobulb size has increased too! Who knows what that will result in. I won't be posting here anymore, my last update.
I will wish you all luck here, I tried to help but it is clear people would rather just have a nuclear reactor but not know how it works. So it's annoying but I'm sick of getting told constantly by people who don't understand my aims that I am talking to a brick wall and nobody is listening.

All my observations are wrong but a picture tells the story better than any opinion - in my opinion so here I will show an example of a pseudobulb that has practically doubled in size since changing what I was fertilzing.



So ironically the bulb is still purple but I think in time that might get greener, that's not really important, the important thing is the experiment was still a huge success and inadvertently things are growing stronger and bigger than ever so I am looking forward to the results this year. I will let you all speculate and wonder what trying something different to the herd might achieve.
Good luck everyone and happy growing even if I will be taking my growing elsewhere from now on

There was an article about a reddit user who spent a year talking to himself but honestly after sening a year on orchidboard I think he did alright, he didn't get criticized once in an entire year

The Redditor who accidentally spent a year talking to himself - BBC News

[K-Sci]

Originally Posted by Shadeflower

Last update.

Although I have a million things to report including getting rid of the reddening to some extent I can tell I haven't been able to convince anyone.

Shade, you did not state your thesis in this post, so I may not correctly/fully understand what you want to convince people of. This reply is based on my best understanding, which may not be completely right.

I think the source of the apprehension about purple indicating a nutrient imbalance is that purple stems and leaves are very well known to occur due to lower temperatures (as in the fall), high temperatures, or strong light. There is a genetic component too, as some orchids are more genetically predisposed to developing purple pigments in vegetative segments. I have a dark-flowered dendrobium that develops purple coloration every fall and a Neofinetia falcata 'Hokage' (火影) that is collected precisely because it develops purple on its leaves in the fall. In my view a small amount of purple or red in an orchid's leaves is an indicator that ideal lighting levels are being provided.

Okay, it is true that the papers you've cited in past threads show that red/purple leaves and stems can be caused by certain nutrient deficiencies. I didn't know this and you've definitely convinced me that this is a fact. But because the purple can also be due to norm al causes, the discoloration can't be used as a reliable diagnostic indicator for proper nutrients.

I was watching a youtube video with someone losing some leaves on their orchids and asking why. I know why but I also know said person from Orchidboard and know they would not listen. So why even ask..?

You've piqued my curiosity. What is the cause and how do you know it could not be a different cause.

An unforseen consequence of this experiement is that growth has dramatically increased. But pseudobulb size has increased too! Who knows what that will result in.

All my observations are wrong but a picture tells the story better than any opinion - in my opinion so here I will show an example of a pseudobulb that has practically doubled in size since changing what I was fertilzing.

What parameter did you change?

So ironically the bulb is still purple but I think in time that might get greener,

How do you know if the purple goes away due to your experiment, or normal seasonal variation in light and temperature?