Light Disruption??? - Orchid Board

Leslie2934 · #1 12-01-2008, 11:04 AM

Hi all, I was having an orchid discussion with my sister in law this past weekend and she brought up something I want to ask about here. She said that she was told (she works for a large florist as a designer and one of the other employees grows orchids) that any disruption in light will affect the way your orchid blooms. I have most of my orchids in my living room/dining room. And at night if I have to go in there and turn a light on this will mess up any bud setting or spike development.

But once I got home I was thinking about this. That dend that I have that didn't bloom for 2 years and is now on it's second set of spikes, is in my kitchen. I turn the light on in there at night and it's blooming.

So I just wanted to get your thoughts on this.

Ok discuss.....

nhman · #2 12-01-2008, 11:16 AM

Hi. I believe that the answer is "It depends". It depends on the orchid species - some don't seem to mind a little light disruption from time to time, some tolerate this disruption frequently, and others get thrown off track easily. For example, I keep some Dens in my bedroom that are subject to frequent light "insults" throughout the dark hours and they bloom right on schedule (provided they are prechilled and left to dry.......) Also depends on the wavelength of the light and the strength of the light used. For example, a low wattage light out of the usual growing range spectral wave lengths will probably not be a problem for most orchids, but turning on a T5 type light would confuse alot of them.

Leslie2934 · #3 12-02-2008, 11:18 AM

So is it safe to say that most would be ok with the normal turning on and off of general lights, say with a max of 100watt lightbulbs? I don't have any of the plant growing bulbs. And I tend to keep my lights a bit lower anyway.

nhman · #4 12-02-2008, 11:24 AM

Probably so - at least with the Dens I believe that you're OK. For most cool growing Dens they need that winter chilling and drying more than anything else in order to bloom. At least mine are not that bothered by the light intrusion as long as they get chilled and dried out during the winter. I have had mine outside until just before Thanksgiving, letting them get exposed down into the 40's and then "neglecting" them until they are in spike. If the pseudo bulbs begin to shrivel, I will mist or water them a little. Beats Cacti!!

Royal · #5 12-02-2008, 11:34 AM

I'd say "it depends" is about right. Some varieties are particularly photoperiod sensitive, but some aren't. I'd play it safe and try to minimize the "insults" (I like this term).

Leslie2934 · #6 12-02-2008, 11:46 AM

What are a few varieties that are photoperiod sensitive. I mostly have phals, but I do have a few others. Just curious.

Royal · #7 12-02-2008, 12:39 PM

I can't recall any specific one - I'm thinking maybe a Sophronitis or a Laelia? I'm not too sure. I would guess that the further it lives from the equator, the more likely that photoperiod has some affect. Just a theory.

camille1585 · #8 12-02-2008, 12:57 PM

Quote:

Originally Posted by RoyalOrchids

I can't recall any specific one - I'm thinking maybe a Sophronitis or a Laelia? I'm not too sure. I would guess that the further it lives from the equator, the more likely that photoperiod has some affect. Just a theory.

I think that near the equator there might be photoperiod affected orchids. They are so used to having the same amount of light all year that a change to less or more light might keep them from blooming.

I know I heard of a species of the catt alliance that needs a certain photoperiod to bloom, but I can't seem to remember the name...

Royal · #9 12-02-2008, 01:34 PM

Cammile, That could be. I was thinking the opposite - those that grow where day length doesn't fluctuate much are accustomed to more constant light and would therefore bloom in response to other triggers like moisture, temperatures, and seasonal weather patterns. Again, just a theory.

camille1585 · #10 12-02-2008, 01:39 PM

I think your theory on equatorial plants is right as well, that moisture and temperature might be more important blooming triggers. But if we only look at photoperiod and nothing else,those further away from the equator respond to changes in photoperiod and those near the equator respond to constant photoperiod.

Of course, maybe both of us are completely off target or maybe making such generalizations is wrong! I wonder if there is anyone here with in depth knowledge of the subject.