Light Filter for Purple Leaves - Orchid Board

newflasker · #1 (**permalink**) 01-25-2008, 05:52 PM

I replace my light by new T8 6500k bulbs. My plants like it: fast growing, leaves turn purple. However, light seems too hot (may be too much IR): leaves a little bit wrinkle so I filter light using green plastic wrap sheets. Purple of leaves gradually disappear and no more wrinkle. I am very happy.

Ross · #2 (**permalink**) 01-25-2008, 06:32 PM

I'm not really sure what you are seeing or saying here. These look like Phal seedlings to me and should be set to 750-1000 FCs for normal growth. Are you using a lightmeter? The film isn't doing anything constructive, in my opinion, other than shading the seedlings. The purple in the leaves might not be a bad thing - it just means lots of bright light. Many folks grow their Phals that way.

calvin_orchidL · #3 (**permalink**) 01-30-2008, 11:21 PM

I think purple pigmentation is a good thing - I have a feeling that it indicates optimal light levels. As for the wrinkling, I believe it may be another issue - I have never heard of light inducing wrinkling. Rootlessness in dry environments, yes .... so perhaps your covering was increasing humidity and thus solved the wrinkle problem. But be careful with that because a completely sealed container may result in fungal growth!!

Tindomul · #4 (**permalink**) 01-31-2008, 10:22 AM

I agree. The wrinkling could be due to dryness, low humidity. You still need ventilation to avoid rot. So i would suggest more frequent misting, possibly use a humidifier, and take the green cover off. Or cover the entire growing area to increase humidity and put a fan in to circulate the air inside. If you already have a ventilation system the way you have it set up now, then you are good to go. I also like purple tinges on my phal leaves. Gives better blooms.

newflasker · #5 (**permalink**) 01-31-2008, 07:38 PM

I have a feeling that purple is good for mature plants but it could be a little bit too much for young seedlings in my case. Both young seedlings inside and outside (deflasked) bottles are wrinkling. In side bottles humidity is more than 90 % and seedlings are wrinkling so humidify is not the issue. The film is very thin and light blue so I don't think it blocks much light. Moreover, my lights are a cheap ones and do not provide a lot of light (only 2 bulbs x 24 inches, 35 Watt total, not few hundreds like your guys). In a plant forum, they use filter to eliminate IR for germinate seeds so I think the film may filter some too hot light such as IR. It's just a theory.

brooke · #6 (**permalink**) 02-01-2008, 08:09 AM

How old are your seedlings? They don't appear to be very young in the pics but I know pics can be deceiving.

I've grown out several flasks of phals and find they will color up in sufficient light. After 7-10 days out of flask and planted into compots of sphag, the plants have adjusted to my humidity levels, I move the seedlings to full sun until about 1 p.m. and then they are shaded.

I agree the wrinkling of the leaves is a humidity issue and either the bark is not staying moist enough or you have lost the roots. If you have any feel for growing in sphag (some people hate it) young phals really do well in it. Phal seedlings actually like to be repotted every three months and always have a noticeable growth spurt after repotting. If you prefer bark, I would suggest a much smaller diameter to hold more moisture.

If you want to increase the humidity around your plants, sit the container in a plastic bag with the top open. Enclosing the entire container can quickly lead to fungal problems which can wipe out young seedlings within a day or two.

Your light set up cannot be too bright for the seedlings. For maximum growth, they should sit about 2" below the tubes.

Brooke