How to bloom a cymbidium

[Paul Mc]

Ok, so a year and a half ago I got a Cymbidium Rosanna (Alexanderi x Kittiwake). I repotted it in a clay pot that was about an inch bigger or so than the plastic it came in. I know since it was so root-bound that I ended up severly damaging some of the roots. After having repotted it, there was immediately some new growth.

I have watered it probably once a week and gave it some slow release fertilizer every 2 months or so. But I still have yet to see any blooms. There are two new growths of leaves emerging (about 3 or 4 inches high now), but no blooms.

I understand that to have blooms they need to feel the temperature differential of night and day, so I left it out until the night temperatures reached the lower 40's during the fall. It is now in my basement grow area under 2 t8's (2 to 3 feet away depending where you measure from - top of leaves or top of pot). I have reduced the watering to about every 2 weeks or when the medium is fairly dry for it's winter rest.

Being new to cymbidiums and after having read quite a bit on here, I'm still not sure why I have not gotten blooms this year. Any advice would be greatly appreciated guys!

[camille1585]

How much light was it getting outside? I don't know where you live, but I leave mine in full sun all day from late may to mid october (with an initial adjustment period of course). Keep in mind that I live at a high latitude (level with the great lakes roughly) so the light isn't as intense as further south.

Mine didn't bloom the year after repotting it, I had way over potted it.

[Paul Mc]

I was wondering about the repotting of it in regards to not blooming this year. Some of the old growth died away and I slowly learned that I was slightly overwatering it during the summer as well (some of the folliage rotted and died).

St. Louis, Missouri sun can be very harsh so I left it under a shade tree where it could get morning and evening direct/dappled light as the neighbors had trees at that time. It was with my Phaius' (which are doing well and blooming). Perhaps I should build up the courage to give it even more light this year outdoors then.

[camille1585]

You want the leaves to be a light grassy green.

That being said, I really have trouble with my cym even though I'm doing everything right.
The first 2 years it didn't bloom, so the following year I stuck it in full sun, fertilized diligently, and added epsom salts to the water (the extra magnesium can help encourage blooming). I got 8 spikes that fall.

But this season I didn't get any spikes. I was in the USA last spring/summer, so left my orchids in the care of my mother. She left it out in the sun also, but wasn't too good about fertilizing. Don't know if that's the reason.

A good cym grower can probably advise you more, since I'm a bit at lose as well.

[BikerDoc5968]

Hey Paul, I'm in Michigan (Detroit area) and I put my Cybidium out on the driveway in direct sun all summer long without any shade. As Camille said about the leave color, mine turn almost lemon/lime colored. I feed them somewhat heavily all summer til about August then just water, reducing the water through the fall and as you have done, leave them out til the overnight temps are in the low 40's. By late September/October I have spikes and by December flowers. The person who may also be helpful on this board is Adam who lives in Cadillac, Michigan.... now I'm not volunteering him but I know he grows some unbelievable Cymbidiums. I know this because I've seen them entered in the Lansing and Michigan Orchid Society shows.

[King_of_orchid_growing:)]

You've gotten good advice from both Camille and "BikerDoc5968" (Howard).

Things that will make your Cym bloom:

1. Bright light, almost full sun. Early morning and late afternoon full sun is okay. Try and avoid mid-afternoon full sun.

The leaves should be grassy green or light green.

2. Low winter temperatures of about 36 F to 45 F at night, 70's F during the day.

Note: They will not bloom after being repotted. So repot immediately after they've finished blooming and the flowers are spent, not just before they're about to produce flower spikes, if they need repotting.

In other words...

Avoid repotting during the winter, instead, repot during early spring.

Other than that, I don't live in St. Louis, Missouri, and I'm not sure what your basement is like, so it's hard to make any kind of assessments in regards to these things.

If it means anything, at least you have someone who lives in the Los Angeles County area to compare with in terms of sun exposure in respect to longitude and latitude.

I grow mine outdoors all year round in full morning and late afternoon sun.

[snviolet]

I too purchased my first Cymbidium at Sam's Club two years ago. It was blooming heavily when i bought it. Haven't been able to get any new bloom since then. Thanks for the tips, i'm probably not fertilizing it enough over the summer. I am also wondering what people do to achieve the low night time temps that some orchids require. I've been turning the heat down really low at nite...the people in the house are a bit chilly in the morning, but if it helps my orchids...i'll try it!

[WhiteRabbit]

Originally Posted by snviolet

I too purchased my first Cymbidium at Sam's Club two years ago. It was blooming heavily when i bought it. Haven't been able to get any new bloom since then. Thanks for the tips, i'm probably not fertilizing it enough over the summer. I am also wondering what people do to achieve the low night time temps that some orchids require. I've been turning the heat down really low at nite...the people in the house are a bit chilly in the morning, but if it helps my orchids...i'll try it!

Indoors, even having the heat set "low" probably isn't low enough, temps should be under 50F at night in fall - it can also be hard to get cyms to bloom if grown indoors because it is difficult to get them enough light.

I have had cyms bloom even when the received NO fertilizer, tho only got 2-3 blooms. I would suspect if you aren't getting any spikes at all, it is more likely to be from insufficient light and/or not being cool enough at night in fall (unless cym is a warm tolerant type).

I have also had cyms spike the same year following a repot, so I don't know if repotting can prevent blooming, tho I do think dividing cause the plant to miss a bloom cycle.

[silken]

Not that its much help but I guess misery loves company. I've had a cymbidium bloom 2 years in a row for me. As far as I can tell, it had the very same culture this past year-except that I re-potted it in early spring right after it was done blooming. I have no signs of blooms this year although there are new growths. I gave it the usual cool treatment in the fall, very good sun all summer and it grows in the greenhouse over winter with a HO T5 right over it and fairly cool temps. I try to keep it a bit dryer for the winter. I guess I will try a little more fertilizer this summer and see if that makes a difference. It doesn't need re-potting again, so will leave it alone.

[King_of_orchid_growing:)]

Dividing does make them skip a cycle.