Cymbidium question regarding cold temps
 

Hi,
My mom bought each of us a cymbidium in the early spring. Given that neither of us has had these before, we've done some reading on them and have found out that they need cool evenings in the fall to flower in the winter/spring.
Mom asked me to ask you folks how many cool evenings and around what temperatures they need for flowering to be triggered. We live in Ontario, so leaving them outside permanently isn't an option, but she was thinking about placing them outside during some cool evenings.

Thanks
Jess

Hi Jess,

Cym's aren't my forte` but a cool period of at least a month is needed. In your area leaving them outside until the nearing of a 'hard frost' would be the way to go. They will take temps down to 32 F (some say lower) but I prefer to bring mine in when the nights start consistently hitting the upper 30's F.
I'm sure someone else with more knowledge of Cym's will chime in.
Hope this helps a little.
Al

I agree with Al. What I've read is that besides lower fall temps is the actual temp difference...apparently they need at least a 15 - 20 deg day/nite change to set spikes and they need it for a several days...what is "several days"? Well, as Al said as long as they don't freeze leave them outside.....

Cymbidium night temps
 

Hello all, just thought that I would weigh in...

I agree that cooler night temps are needed to initiate and set spikes for cymbidiums, but I would disagree with the length of time given as a guideline. Remember that many of the species Cymbidiums are from areas of higher elevation--they experience bright warm and (in spring/summer) very wet days, with much cooler nights. Fall brings drier clearer days and even cooler nights, with winter offering little in the way of steady precipitation, but constant cool temps. That all being said, try to aim for a consistent difference in day/night temps year round (I would say 15F as a minimum), with a period of cooler temps toward the end of fall and on into winter. Please also remember that during the spring and summer your plants should be getting heavy watering and feeding, as well as high light (the leaves should look almost chartreuse in color); toward mid fall stop feeding your plants, cut back on water by about half and keep them as cool as possible w/o freezing them. You should be seeing spikes beginning to elongate at this time. Keep in mind that when you move them inside as fall progresses, you will need to maintain them with nights in the 50F range or you will run the risk of blasting your spikes. Also bear in mind that the longer your plants have to mature spikes at cool temps, the more intense the color of the flowers and the better their substance will be.
*If, however, you are growing any of the warmth tolerant cymbidiums (Gold Elf, Chen's Ruby, Tiny Tiger, etc), you will not need the pronounced cooler temps in fall (most of these have some of the warmer growing Australian cymbidiums in their parentage)--they will resent the cooler temps, performing better in high light with warm nights.
Hope this helps you a bit,
Good growing!
Adam

Sylorna, follow Adam's advise as close as you can.
He grows and blooms the most fantastic Cym's to be seen. If you can't give your plants the exact conditons he recommends, come as close as you can.
Different parts of the country/world offer different conditions and we can't always do the perfect thing.
Just try, that's all we can ever do.

Thanks for chiming in Adam, I was hoping you would catch this thread along the way!!

Al

Thanks for the praise Al...but it's all trial and error (and reading...lots of reading :))
Adam

Actually when the plant blooms has a lot to with when the cool period is needed. The big himilayan plants "like"
a temp swing of 20 degrees F with a high of 75 and a low of 55 in July and August. Thats optimum and rarely achieved (especially not here in Florida) Generally though cymbidiums like cool night temps as has already been stated. The whole process of initiating spikes is complex. I dont believe anyone has mastered a procedure to get cymbidiums to bloom on Que - I sure would like to know if anyone has.

wow! sounds really tough!
I will forward the info and suggestions to my mom, who has kindly volunteered to cool them.
After reading all this though, I'm thinking we may be stuck with two very large pots of leaves from here on in.

At least my dracula is growing spikes!

And also....thank you all :)

If you really want to delve further into this subject I would suggest that you look at the observations of Frits W. Went from the 1950's when he was doing research at CIT Pasadena--in a nutshell it was observed that Cymbidiums kept under 16hr photoperiods with 20C (68F) days and 14C (57F) nights would remain perpetually in flower--that is to say, all emerging buds on a pseudobulb will develop as inflorescences. Theoretically if one wanted to go to the expense of maintaining a large collection under glass for use as cut flowers/pot plants using this research as a launching point, I think that you could indeed get your cymbidiums to bloom "on que". I, for one, will stick instead to Dr. Went's guidelines of long summer days, differential day/night temps, with cooler fall/winter nights (10C/50F), and let my collection do its thing. Just my 2 cents
Adam

BTW: if you are interested in Went's work he wrote an essay briefly highlighting these points for the fifth edition of Orchid Biology...additional information can be found in his book The Experimental Control of Plant Growth

If I lived in Canada I would put them outside as soon as the chance of freezing is past and bring them in when it gets cool enough to freeze in the the fall. I live in Florida not but did live in Connecticut - I think your conditions are similar.

Is there some way to get access to Mr Wents oservations. My first intrest in cymbidiums was when
living in California (Corona) the collection moved to Connecticut where I was told that few people grew cymbidiums but was appreciated for showing the few I had by a gentleman named Gustov Melquist who was famous for his research at Missouri Botanical Gardens. When I moved to Florida I was told cymbidiums were impossible to flower here that was 20 years ago and frankly I have found ways to bloom a lot of cymbidiums.. Dont give up but always look for more information!

I live in birmingham, UK and I grow mine outside all year, just sheltered from rain and the worst of the frost. And they bloom every year like clockwork :-)

Hi Sylorna,

You've already got some great info from the members, check out the link from clouds orchids ...

Cymbidium Species and Hybrids

Gloria,
The temperature and light information in your link are sure close to right but I sure do water and fertilize differantly. I would looks somewhere else for instructions myself. Please compare your culture sheet to the one on this site Basic Cymbidium Culture

I stick mine outside from May to October, and bring it in when night temps hit 5°C. The first year the spike blasted, last year it didn't do anything (lack of fertilizer and overpotted) and this year it didn't do much since last summer was very cloudy. The leaves where a dark green, and I was right not to expect much from it. This year everything is perfect. Lots of food, light and temperature differences. I'm crossing my fingers for some spikes next time around!