Inducing blooms in Cymbidium
 

Hi All,

I have a Cymbidium "Sweetheart Elegance" that was given to me by a friend who wasn't really giving it what it needed.

I have had it for about a year, and I haven't managed to get it to bloom. The plant is on a west facing window (I literally have NO south facing windows) where it gets sun that allows my zygos and oncs to bloom.

Is my lighting too low (what light levels are best, I have a meter)? Is there something else that triggers Cyms to bloom?

Cyms need bright light--outside in the sun bright light. They also need a temp change of around 50 degrees in the winter.
Have you checked the roots and repotted lately?
Are you feeding weekly?
Joann

The roots are going like gangbusters, and the plant is putting up new growth. I fertilize weakly, weekly.

I don't know if a 50 degree temperature fluctuation is even possible here. Seattle is very temperate, and is usually in the 40's-50 (F) all winter, and 70-80's all summer. Add to it the super gloomy few years we have had here (yes, I said YEARS) and maybe that is why I haven't seen any blooms.

How many hours of full sun will it need? We are on the north side of our building, and so providing full, direct sun can be hard.

If you keep the plant outside during spring-fall it will get the temp change to the 50's or a bit below. I keep my cyms in full eastern sun until about 1:00pm then the tree shades them. They go outside after the last frost and stay until the first frost.
I have large east and south windows but never could get one to bloom inside, so out they go and they seem to like it.
Joann

not a 50 degree fluctuation in temps - but night temps below 50 in fall ... tho some are warmth tolerant, and don't need the cool period to induce blooms, but the cool period won't harm them any

and as Joann said, lots of light

The Idea that a fall temperature drop will cause flowering is all wrong. If it were correct cymbidiums all do well in Florida. Only the heat tollerant cyms do well here. The mechanism that causes flowering is day night temperature swings in July and August. Differant heat range cymbidiums require differant swings. The book "Heat Tolerant Cymbidiums" gives a good explaination and will help anyone get cyms to bloom better - due to a better understanding.

thanks for that info - I hear different things- what is the temp difference needed?

I've grown cymbidiums on the West coast and here in Hawaii. I suggest the following details. Most standard sized ie cool growing cymbidiums require a day to nighttime differential of about 15-20 degrees F. This is to Set the spike or initiate the flowering and generally this is about 3 months in advance of the spike showing. Then once the spike initiates most cymbidiums require a nighttime temperature of less than 55-60 degrees F. If the nighttime temperature is too high you will see significant buddrop.
I suspect that in your case by having the cymbidium indoors you do not have the temperature variation required. Most of the warm tolerant cymbidiums are really temperature independent and will flower without these strict requirements. I hope that clarifies the issue.

Thanks for all of the information!

This Cym is apparently a "cool grower". I have moved it outside in an area where it will receive better light, and undoubtedly better temperatures. A 20 degree shift between day and night is pretty standard in the summer here, so hopefully that will be enough to do it. Our summer temps rarely shift into the 90's, and never more than for a few days, is there something I should do to protect it at that point?

Right now, we are lucky if we get a 10 degree shift between day and night, but once the cloud deck rolls back, we should get some fluctuation.

Thanks for the help with this one. This isn't really an orchid I would choose for myself, but since it is taking up space, I might as well get the darn thing to bloom!

Cyms seem to love the outdoors - leave them out till until there is a danger of frost. If you must move them in - find a cool place with good air movement. They are quite hardy and forgiving otherwise.