Light levels and developing pseudobulbs on cattleyas

[mossmac]

Hi there,

I was just wondering if cattleya orchids should be placed in slightly lower light levels when they have new pseudobulbs developing?

I ask this because the leaves on a new pseudobulb of one of my cattleya orchids are a very mottled purple colour and it looks like one leaf has a small area of 'sunburn' (a dried out, brown patch). The orchid is on a north facing window (in Australia). The window receives bright light, but not direct sunlight. The other older leaves on the orchid are all a uniform mid-green colour without any purple colouration.

As I am new to cattleya orchids and have not had my cattleya for very long, I would really appreciate any help/ advice.

Mossmac

[ronaldhanko]

The purple color is usually a sign that the plant is getting good light and is nothing to worry about. The sunburn comes from moving a plant into bright light without first "conditioning" it - not much different from a human. Most of us can't go out into full summer sun for a long time after being indoors all winter without getting burnt.

[johnblagg]

I keep mine under a 250 watt high pressure sodium light and I get the purple color but I have finally got it at the right height to just be somewaht reddish purple but they can be reddish but too much red is a sign its too much light

[ronaldhanko]

It is extremely unlikely that a Cattleya is getting too much light in a window where it gets no direct sun.

[mossmac]

Thank you very much for your replies. I am somewhat surprised by how purple the new leaves are, considering the plant doesn't receive direct sunlight. However, the light we get here in South Australia is incredibly intense and the glare from the light coming in through this particular window really does make you squint! There is also additional glare from the surrounding white walls outside in the garden.

The plant has been on the windowsill for around three months and it has developed its new pseudobulb since being there. I guess the change from lower winter/ spring light levels to intense summer light levels might explain the small area of 'sunburn'.

I was wondering if the leaves will always remain this purplish colour, or if they will 'green up' more as they age? Also, what do I do about the small sunburnt area of the leaf? Do I just leave it or does it need to be 'treated' with something? It is a small, dry, brown area not much bigger than a fingernail.

Mossmac

[johnblagg]

some get more purple than others. I have one that produces a purple bloom and it gets very purple compared to the ones that bloom yellow and orange ...It does or at least mine did turn back to green whan I raise the lights a inch or two because I had read someting about the red pigmentaition can cause a poisoning effect ...I dont know this as fact just hear say.

The sunburnt spot is just going to be a brow dead spot if it is very burnt and will be ok.