Cymbidium goeringii "Fuji no Yuubae" Mid January 2021 UPDATE 日本春蘭「富士の夕映」

[jokerpass]

Mid January is a great time to see where the flower buds are during their development. This year, this orange Japanese variety is a bit of ahead of schedule. The flower buds have all came out from the sheaths and the flower stems have already elongated somewhat. This should in full bloom in 2-3 weeks and the flower stems should elongate as the flowers keeping maturing. Will take better pictures once they are in full bloom. There are a total of 5 flowers this year which is better than last year.

 

[DrLeslieEe]

The capping made such a huge difference.

Explain scientifically why this occurs again? Is the sunlight triggering chlorophyll for photosynthesis?

 

[jokerpass]

the buds must be developed in the dark for 6 months or more during the year because this is how long it takes for the flower to bloom (from budding to blooming). It is the combination of the darkness and the extended period of consistent cold (0C-10C) in the winter that resulted in the vibrant colour.　Below is a C. goeringii "Fuji no Yuubae" I found on the internet. When it is not capped, the flower colour is dull orange and green. My Taiwanese Cymbidium vendor told me that although it is possible to bloom them in Taiwan, when the coloured varieties bloom, the colour is off and I think it is because Taiwan is too hot.

 

[TyroneGenade]

I need to get some of these! How low a temperature can they stand?

 

[monocotman]

Dr Leslie, it sounds like you are right. The caps stop chlorophyll development and result in brighter more vibrant colours from the underlying anothocyanins and flavonoids,
David

 

[jokerpass]

Monocotman: It is also the low temperature. As I mentioned above, it is BOTH low temp and lack of chlorophyll. Even when it is covered with aluminimum foil, but if you don't meet the low temp requirement, the colour won't be correct either.

TyroneGenade: C. goeringii is a seasonal orchid so it has 4 conditions throughout the year (1 condition for every season). So, watering, lighting, and temperature are adjusted accordingly to the changing season. It is very hard to explain. However, here is the temperature requirement:

Spring and fall: 15C-19C (intermediate)
Summer: 25C-30C (hot to warm)
Winter: 0C-10C (cold)

C. goeringii is NOT a flexible orchid like many other orchids. The changing seasonal conditions must be met; otherwise, it will not do well for you. The temperature range stated above must be strictly followed (ie. no higher or lower). In Asia, the temperature goes up and down slowly throughout the year like a staircase. My Japanese Cymbidium vendor told me tha the lowest C. goeringii subsp. goeringii can go is -5C.

 

[DrLeslieEe]

Great info Mike. Thanks.