What's a good amount of light for phals?

[KatyaB]

Its been about a month now since I've decided to give my orchids more light. During the day they sit on a south facing window sill. Oncidiums are happy and growing. Phals have also started producing more leaves, with one issue: some of the top leaves are turning light green and getting funny spots on them. What is it? Should phals get less light? I've heard such differing advice before...

[Bird Song Farm]

Originally Posted by KatyaB

Its been about a month now since I've decided to give my orchids more light. During the day they sit on a south facing window sill. Oncidiums are happy and growing. Phals have also started producing more leaves, with one issue: some of the top leaves are turning light green and getting funny spots on them. What is it? Should phals get less light? I've heard such differing advice before...

Phal leaves will burn quite easily in direct sun. Now that the position of the sun in the sky has changed yours might be getting to much sun.
Phals like an Eastern exposure with only the cool morning sun.
Hope this helps some.
AL

[RosieC]

It does sound like your Phals are burning and getting too much light.

As Al said Phals don't generally like direct light. All mine (except bellina which like higher light) are in an easten window and seem quite happy.

[Orchid126]

Feel the leaves. If they are warm, pull the plant back a few inches. Inches, mind you, not feet. Light drops dramatically for every few inches away from the source. Keep doing this until the plant is getting as much light as possible without burning.

[trdyl]

As Al and Rosie have said eastern windows are best for most Phals.

[orchidsamore]

All orchids will get lighter green as the plant needs less chlorophyll to produce food in high light.

You are still a long way from burn but watch it.

Oncidium like 2000-2500 foot candles of light and Phals need only 1000-1500.

[sii]

I wonder if the growing zone that we live in makes a difference. In my case, I think I'm in zone 5 and from what 'microscopic' progress I see, phals seem to like my southern window.

[Bird Song Farm]

Originally Posted by sii

I wonder if the growing zone that we live in makes a difference. In my case, I think I'm in zone 5 and from what 'microscopic' progress I see, phals seem to like my southern window.

Not quite sure by what you mean by "microscopic" progress. If your phals aren't growing as fast as you think they should be it could be a question of to much light..............

AL

[sii]

Originally Posted by Bird Song Farm

Not quite sure by what you mean by "microscopic" progress. If your phals aren't growing as fast as you think they should be it could be a question of to much light..............

AL

How will I know that I'm giving them to much light?
I have the vertical blinds turned facing down and they are about a foot away from the window on my desk. They receive only the morning sun (sun has moved away from this window by noon) I've touched the leaves and they don't feel hot. The window in this room has been open for the past few weeks, as we've had some cool weather and don't need the AC on.
They have all recently been repotted in sequioa bark and all but 1 are in clear pots. The other is in clay. I've been kindly reminded that I need to wait until the roots are silver before I water them. I've held off on fertilizer. I've even collected some rain water and am using that to water them. This is a learning curve for me. Any advice?

[Bird Song Farm]

Originally Posted by sii

How will I know that I'm giving them to much light?
I have the vertical blinds turned facing down and they are about a foot away from the window on my desk. They receive only the morning sun (sun has moved away from this window by noon) I've touched the leaves and they don't feel hot. The window in this room has been open for the past few weeks, as we've had some cool weather and don't need the AC on.
They have all recently been repotted in Sequoia bark and all but 1 are in clear pots. The other is in clay. I've been kindly reminded that I need to wait until the roots are silver before I water them. I've held off on fertilizer. I've even collected some rain water and am using that to water them. This is a learning curve for me. Any advice?

Here is part of the problem. Everyone has their own way of growing, not only phals, but other species too.
It's a process of learning what works for you. It sounds like you are doing everything right. I would fert. the plants at least once a month. I use the "weakly, weekly" method. I also put a few drops of KLN in the water each time I water. KLN is a rooting hormone and is available on line........search e-bay for it.
Your plant in the clay pot will probably dry out quicker than the others as clay is porous and dries the medium out faster.

Leaf color can also give you a clue as to light requirements. Most hybrid phals should be a nice medium green color........a light green leaf usually means to much light. (There are exceptions of course) and a really dark green might indicate to little light.

I'm not familiar with Sequoia bark, most bark mediums have other ingredients like LECA (clay balls), perlite, CHC, etc. You might think about changing your medium to a good orchid bark mixture.
Maybe the Sequoia bark has something in it that phals aren't especially happy with?

Believe me, we are all on learning curves. LOL

AL