Is this sun burn ?

[yvonni]

I had most of my orchids inside , decided recently to move them to the outside . Most of them seem to be ok but a couple of them have been showing what I think are signs of sunburn so I'm here to ask the experts . What do you guys think ?

[yvonni]

Oh and it definitely wasn't this color when I put it out there

[wetfeet101b]

That is not sunburn.
Hard cane dendrobiums usually develop a purple tint if they receive plenty of sunlight, but not enough to cause sunburn.
Depending on the variety, some would have the entire leaf turn purple while some would just have the edges turn purple or red.

Some dendrobium growers prefer to see this pigmentation as it is an indication that the plants are just a hairline under their maximum tolerated light exposure, which translates to a large potential energy gain for the plant if all other requirements are met.

[sand_tiger86]

^ Exactly what he says. It's definitely, in my opinion, a favorable result. You'll find that if you put it back in away from the light, the red will go away. Also, once that cane matures the red will most likely go away as well...the newer growths get that red tint very easily.

[Halloamey]

The red color is due to the pigment anthocyanins which are like a natural sunscreen for the plants, this definitely indicated higher than optimum light for the plant, even though better than growing in less than optimum light I would not say it is ideal. I would try to reduce the intensity of the light a bit or move it slowly into these high light conditions.

[Magnus A]

I showed this effect in a photo with some more information not long agoe.
As Amey Bhide point out, the red coloration is due to the anthocyanins. When moving a plant from low light to high light this is a common reaction. Plants can be adopted to high light and then the red/purple coloration is less pronounced.

http://www.rv-orchidworks.com/orchid...hocyanins.html

[yvonni]

So what's the consensus here ? Should I leave them (it's 2 that look like this) , where they are or move them into a lesser light situation? I know Amey thinks I should move them and I have already because I freaked out when I saw it , but I would still like to know what you other guys think also . Thanks everyone all the same for all your help

[mujacko2002]

Mabuhay!

i have this kind of thingy happening to some of my orchids drenched in full sun everyday. I just leave it there.

[catttan]

I agree with Amey that it has been exposed to a tad too much sunlight ( note the burnt tip on the lowest leaf) but it also shows that the plant is acclimatizing to the higher degree of sunlight (no sunburn on the later leaf growths). Being the lazy bloke that I am I usually leave such plants alone but if you prefer darker green shiny leaves then move it to a shadier part of the grow area.

[yvonni]

Thanks guys for all your help . I think I will stick with my decision to move them into a more shaded area .