24 hour photo period?

[marydaniellesantos]

Originally Posted by Brotherly Monkey

No worries and I really appreciate any and all input. I just there is really little reason to limit yourself by "what's in nature" when you are already growing in such an artificial environment.

Very true.

[Undergrounder]

Originally Posted by Brotherly Monkey

couldn't this be dealt with through adequate ventilation?

By ventilation you mean refreshing the air with fans/windows, etc?

300ppm CO2 is what is naturally in the air, and having good ventilation would not increase the total amount available, only ensure that the 300ppm air is refreshed as it depletes. The effect is to overcome CO2 depletion, although it is comparatively a very small effect.

I know that people grow Cannabis under constant light - but whether they get significantly more growth or not I don't know. Cannabis are a much higher light plant than orchids, so more light may be beneficial for them where it is not needed in orchids.

[Brotherly Monkey]

Originally Posted by Undergrounder

By ventilation you mean refreshing the air with fans/windows, etc?

300ppm CO2 is what is naturally in the air, and having good ventilation would not increase the total amount available, only ensure that the 300ppm air is refreshed as it depletes. The effect is to overcome CO2 depletion, although it is comparatively a very small effect.

I know that people grow Cannabis under constant light - but whether they get significantly more growth or not I don't know. Cannabis are a much higher light plant than orchids, so more light may be beneficial for them where it is not needed in orchids.

Yeah, I get most of my user reviews and technical information on lights and indoor gardening from Marijuana forums. And while doing some research on converting a space to grow ultra-highland neps, i came across the info about 24 hour light cycle for vegetative growth.

What got me interested in the idea, is that they general only use about half the wattage doing a 24 hour light cycle, than when they switch over to a shorter cycle for flowering, and are able to get around the whole CO2 issue by constantly venting the room


I highly doubt it would be anything I just haphazardly tried. But am considering moving my light cycle above the 12 hour mark. maybe starting with 16 and working my way from there.

Interesting enough, while doing a bit of research last night, i came across an abstract describing some research looking into extended photo periods with orchids, and claimed that they only ran into issue when they did a complete cycle of 24 hours, which prevented flowering

[Brotherly Monkey]

Originally Posted by johnblagg

I used a month of long days and then three or four 24 hour days and then back to a short day cycle for about a month and repeated the cycle ...I got really good growth throught the winter and three sets new leads two of which are mature and the last set is taking forever since I went to the same schedual as natural for the summer ...

So you're saying you were able to force additional periods of vegatative growth in your cats?

[Undergrounder]

Originally Posted by Brotherly Monkey

What got me interested in the idea, is that they general only use about half the wattage doing a 24 hour light cycle, than when they switch over to a shorter cycle for flowering, and are able to get around the whole CO2 issue by constantly venting the room

I highly doubt it would be anything I just haphazardly tried. But am considering moving my light cycle above the 12 hour mark. maybe starting with 16 and working my way from there.

I think 'the whole CO2 issue' they're getting around is CO2 depletion, which is not so much a problem for us. We don't need ultra bright, hot lights to grow orchids, and don't need to manage heat, smells and ventilation as much.

For us, the 'CO2 issue' is more to do with whether or not to increase overall CO2 levels in the atmosphere. Interestingly, the air in rainforests has about 60% more CO2 at night than during the day (due to the night-time respiration of rainforest trees), which is one reason why many orchids selectively uptake CO2 at night.

CAM orchids in the wild are effectively getting 60% more CO2 than we give them. By growing only CAM orchids indoors, we are effectively hamstringing this natural advantage.

I highly doubt it would be anything I just haphazardly tried. But am considering moving my light cycle above the 12 hour mark. maybe starting with 16 and working my way from there.

If i were going to design an optimal growth chamber for Phals, i would have a 15 - 20 degree C temp dark period of about 8 hours with elevated (1500ppm) CO2, vented and refreshed every hour. Then a 25 degree C light period of 16 hours with 800fc - 1200fc fluoro lights. And the whole system on hydro or semi-hydro. Balanced ferts between at 250ppm if flushed monthly and 600ppm if flushed daily. That's my guess where optimum growth would be!

Interesting enough, while doing a bit of research last night, i came across an abstract describing some research looking into extended photo periods with orchids, and claimed that they only ran into issue when they did a complete cycle of 24 hours, which prevented flowering

I think that's the Lopez article? And yes they only used C3 plants like Miltonias, Brassias and Oncidinae - hence they were fine with 24 hour light.

And all of those showed peak growth at a photoperiod of 14 - 16 hours, with plants under 24 irradiance performing the same or significantly worse.

[stefpix]

I do not understand the long night / short days photoperiod and viceversa. Cattleyas grow often close to the equator where it is constant 12 hour days/nights throughout the year. It does not make sense to make shorter days in the winter. Anyway the sun is more intense than fluorescents, so anyway it is hard to recreate the same conditions

[Brotherly Monkey]

Originally Posted by Undergrounder

I think that's the Lopez article? And yes they only used C3 plants like Miltonias, Brassias and Oncidinae - hence they were fine with 24 hour light.

And all of those showed peak growth at a photoperiod of 14 - 16 hours, with plants under 24 irradiance performing the same or significantly worse.

I'm not sure. it was pretty late when i found it so i just skimmed over the abstract and was hoping to try and track down the full article today. But sadly, my power went out last night, and I didn't think to book mark it.

Do you know the full title, and where I might be able to find it online?

[Undergrounder]

Originally Posted by Brotherly Monkey

I'm not sure. it was pretty late when i found it so i just skimmed over the abstract and was hoping to try and track down the full article today. But sadly, my power went out last night, and I didn't think to book mark it.

Do you know the full title, and where I might be able to find it online?

Lopez, R., G. (2003). Effects of Photoperiod and temperature on growth and flowering of six orchid hybrids

PM you're email, ill send it

[johnblagg]

Originally Posted by Brotherly Monkey

So you're saying you were able to force additional periods of vegatative growth in your cats?

Actually since these were my very first catts ever I realy dont know but I thought that getting 3 or 4 new growths from August to Jan was pretty good I was expecting 2 at most .....and these were very small plants 3 to 4 years from bloom they said when I bought them.My actual goal here was not more growths per season so much what I want to see is if the cycling from short days to long days will shorten the time it will take to bloom.It will be one full year in August

[jkofferdahl]

Originally Posted by Brotherly Monkey

Meh, I don't buy into the "mimic nature" argument. I mean, in nature, plants don't grow in my basement under artificial lights, right?

Sounds to me then like you asked a question but don't care for any answers that differ from your preconceptions. So I say go for it - give them lights 24/7. Let us know, in about a year, how they do.