Orchids A FEW Hours of full sunlight versus Many hours of cloudy "dayight"

[citywildcat]

I live in a state where the winters get rather cloudy, grey, and depressing.

I'm lucky to have a southwest exposure for my mini greenhouse but I'm wondering what to do on the days when I don't get any sunlight (cloudy daylight) at all. On sunny days, I have to pull the blinds for all but a few hours.

My question is: on the days when there is no direct sun, are the plants still getting sufficient light when there is NO sunlight (COMPLETELY cloudy)? On completely cloudy days, the blinds are open all the time and I even have a grow lamp I turn for a few hours on those days.

We are getting into that "completely cloudy" type weather. I would appreciate some input on how to handle the lighting issue.

MANY THANKS!

CWC

[jhodgson]

I live near Chicago, Illinois and I have been growing mostly Cattleyas in a sunroom for over three years. There cannot be many more places that have the short, dark winter days as here, but my orchids seem to do fine over the winter. I do not do anything special concerning lighting during the winter. But, since the sun is lower in the sky during this period, when it is bright outside the sunroom does get more light than during the summer, though the duration is a lot less than summer.

The biggest trick is keeping them dry during the winter and maintaining the humidity near 50%. I cut back a lot on watering, and only water when there is a bright sunny day so the plants will dry before nightfall.

[raybark]

I'll agree with Jim, but keep in mind that even though the sun is lower in the sky, so its rays can get in the windows easier, the light has had to pass though a lot more atmosphere, so is a lot less intense in the winter.

You basically have two options - realize that the plants are going to do far less growing with less light intensity, and adjust your culture accordingly, or add some supplemental light. As you're already doing that, personally I'd put the lights on a timer, staying on for about 14 hours a day all winter - maybe even all year.

[citywildcat]

Great ideas/thoughts, you guys! It makes sense. JHODGSON, I like what you said as your climate is similar to mine (outside Detroit). My fan blows the daylights out of my orchids & I water some every day even now! My problem is having TOO much light in the summer and about right in the winter (maybe) except for the stretches of cloudy days. I won't know for sure as this is my first winter growing indoors. When I first grew indoors, this was about 20 years ago and I had many, many shelves of plants but made the big mistake of not having any humidity or air circulation.....DUH! I now have a mini greenhouse/much more sun, and the factors for successfully growing but less space. I invested in a fan, thermometer/hygrometer, etc. humidity levels never going below 60%. JHODGSON, do you supplement for humidity and air circulation?? The reason I ask is you mentioned dampness in the winter. Would a supplemental fan help you out with that? I prefer too dry than too wet which is how I ended up with the fan. If you see a little greenhouse flying over Chicago through the air, you'll know I turned my fan on HIGH by accident and it blew through the roof, L O L!

[kspalding]

It would depend on the type of orchid. Some require more light than others.

[78Terp]

I'll agree with Jim, but keep in mind that even though the sun is lower in the sky, so its rays can get in the windows easier, the light has had to pass though a lot more atmosphere, so is a lot less intense in the winter.

You basically have two options - realize that the plants are going to do far less growing with less light intensity, and adjust your culture accordingly, or add some supplemental light. As you're already doing that, personally I'd put the lights on a timer, staying on for about 14 hours a day all winter - maybe even all year.

I am new to orchids and this is my first winter season growing them. So my question below is a totally serious question.

I read that too long of light (how long the plants are lit each day cycle) in the winter can affect the blooming cycle. I'm hearing <10 hrs during the winter.

Is that not a concern?

[citywildcat]

Jim, If I left my supplemental lighting on all year round, I would have some seriously burned orchids as I have both an eastern window and Southwest window as well. I am looking for some shade cloth so I am ready for next summer :-( (in late September even, my Vandofinetia got leaf burn/MY fault. About five years ago I had a small fruit tree on my kitchen table that actually bore fruit.). But I am getting more lighting for these winter months!

[SeanHoutman]

I am new to orchids and this is my first winter season growing them. So my question below is a totally serious question.

I read that too long of light (how long the plants are lit each day cycle) in the winter can affect the blooming cycle. I'm hearing <10 hrs during the winter.

Is that not a concern?

That can be a concern, but day length is more likely to be important to species orchids than hybrids.

[coeruleo]

well......... i would just like to toss out the idea of 'learning what you can give your orchids, and buying orchids that like it' as a practice. let your growing area's weather pattern be your guide to get orchids that like it where you are. you will get more blooms, and more enjoyment of the hobby. otherwise you will need to invest in some kind of life support system, like green houses, heaters, coolers, grow lights etc. i try to go the low tech route.

[raybark]

That can be a concern, but day length is more likely to be important to species orchids than hybrids.

Sorry, but I have to jump on such a general statement, Sean.

1) Not all species' blooming cycles react to changes in the photoperiod.
2) Hybrids of those that do, will also do so.

For example, I am not aware that any phalaenopsis species do, while many of the large, "classic" cattleya hybrids do.

Orchids are such a diverse group of plants, that it is really tough to paint any aspect of growing them with a broad brush - I know every time I try, there is ALWAYS an exception, and with some digging, I often find that exception isn't as "exceptional" as I'd thought!