Day length questions?
 

Hello all:waving!!!! its time to bring in the orchids!!!! in about 2 days the temperature at night will be too cold for my plants(mid to low 40's) its sad!!!!

I have trouble with how early for the timer to turn the lights on and how long to have them stay on? What day lengths are you guys using? i want my lights to reflect nature to follow the day lengths of fall then winter then spring..... Is that wise? what is the recommended procedure?

i dont want to confuse the plants! the Species types are starting to wind down for fall and winter, and the ones that bloom in fall/winter are setting up for their bloom(Sesquipedale leonis), so i also dont want to interrupt that either!!!

Can you help me with this

Part of it depends on what sort of orchids you have. I think that there are Catts that bloom is response to day length, for example.
I think the average length of time that the lights are on is between 12 and 16 hours a day for plants that don't really care about duration. I used to leave them on 16 hours, but my Phals were getting excessively purple so I brough it down to 13. I work in research on plants, and all of our greenhouses are on a 16 light - 8 dark cycle.

As for the time you turn them on, I think it's a matter of personal preference, especially if it's your main light source. I like to see my orchids in the evening, so I set the timer so lights turn off at 11pm.

Probably in the next few days, they will go a (10) to 12 hrs duration of lights with 1 day a week no lighting at all.
By mid feb they go back on 14 to 16 hrs of lights.

Ohh ok!! here is my plant list let me know if there are any that i should be concerned about!!! i really like both of your set ups!!!! i like the idea of a day of rest! its like a orchid Sabbath day! last year i had the lights come on at like 5 am and it woke me up and my brother i think i will have them come on at 6 am that's doable 10 to 13 hrs and as spring approaches to 16 hrs other thatn the Labiatas i think the other catts respond more to wet and dry seasons and heat....... anyways heres the list let me know what you think.

Angraecum didieri (Small Buds)

Angraecum distichum (Small buds)

Angraecum leonis (New Growth)

Angraecum sesquipedale( Spikes initiating)

Blc. Chia Lin 'New City' ( New Growth)

Brassavola. Little Stars (In Sheath)

Cattleya intermedia var. orlata (New Growths)

Cattleya Labiata var. alba (Currently in Bloom)

Cattleya Labiata var. rubra (Bloomed a month ago)

Cattleya Maxima (New growth Just starting)

Cattleya Warneri var. concolor ( Not active)

Dendrobium Noid (Maturing growths)

Laelia Pacavia (Maturing growths just showing sheaths)

Laelia Purpurata var. carnea (Maturing a Growth)

Phalaenopsis Bellina 'Montclair' (Blooming)

Are there any i should be concerned about as regards reacting badly to day length? Im really excited!!!! i have another shelf 2 feet wide and has 2 1/2 feet of head room!!!! the bottom shelf will have 2 lights and the new shelf will have 3!!! I need some more winter blooming types so that it wont be all green this
winter!!!!

I have the Chia Lin and the Sesquipedale and the leonis and maybe the dideri....Any suggestions for winter bloomers that stay compact and make an impact? fairly easy care?

I have all mine on the same time. I change to 12 hours a day when we go off DST and back to 15 when we go on again in the spring. I'm on 6am - 9pm right now and will drop back to 6-6 at the end of DST. I've gone with the theory that since man made lighting isn't close to natural sunlight (contrary to advertisements) the longer duration makes up for it somewhat.

Why do a shorter amount of time in the winter? If anything it's that time of year where they are going to need extra light the most. If you are doing this to mimic natural daylength, don't forget that many orchids are from the tropics where the daylength hardly varies at all over the course of a year, and is roughly 12-12. The only reason we do more hours is to make up for the lower strength of the lights compared to sunlight.

Hi Gloria. Why 1 day with no lights at all?

Bill

Hay Bill,

Well not for any particular reason, 'cept I have to talk to hubby and the dogs sometime, lol! Actually I pick 1 day a week not to worry about anything and they just happen to be in the line up of things. We all need a break eh? :)

Orchids don't suffer cos' there is a few hrs of less light in the winter. I've orchids that don't even need lights for months at at time. Some dens and catts need the less duration of lights or they won't bloom. I also back off on the watering too - they don't need asmuch.

You must remember when growing in home under tubes the lighting is more consistent. I'm not looking for sunlight simply becos' we don't get much through out the winter months. My orchids don't suffer becos' of this and I enjoy the break cycle of the winter months :)

Cam!!! That is an excellent point!!!!!!!!! I for get these things!!! thanks!!! That was my thinking, that i was mimicking nature, i will leave that idea behind now with this added information!!!

so anywhere from12-16 hrs is good, thats the general consensus?

I will not cite the sources, but the studies that have been done on orchid flowering show that some orchids flower in response to a period of short days (some Cattleyas), some in response to a period of cooler temperatures (some Phalaenopsis), some to a combination of these (some Miltoniopsis), and many we haven't really studied well enough to figure out what makes them bloom. In a mixed collection, the best hybrid set of conditions to trigger blooming in various genera that are ready to bloom is a period of 4-8 weeks of short days followed by a period of cooler days (< 72F) and nights for 4-8 weeks. The definition of a short day is going to depend somewhat on the source of light the plants are getting, but probably means in the 11 hour range for sure. In the wild, Phalaenopsis rarely grow where days are shorter than 10.5 hours. Most other genera grow even closer to the equator where days are rarely shorter than 11 hours. Some under-lights settings might need to be a little longer this but I don't think it has been carefully studied with different light sources.

Some orchids of course will start to bloom after you have finished with all of your Fall/Winter vernalization and we call them Spring/Summer bloomers! Get a mixed collection and you can have flowers all year long.