What causes this?????? They show up once in a while, and I really can't trace to any culture thing.
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What causes this?????? They show up once in a while, and I really can't trace to any culture thing.
I have one right now on one of my catts. Its been there for quite a while. I just figured it must not have gotten something it needed when the bloom was forming and it just stopped at the sheath. Hopefully someone will give us the answer as to why this happens?
Most of the time I see them on catts that are just approaching blooming size. After that, I think maybe fluctuations in temps may effect mine...but I will be curious what others say.
I have several catt hybrids that have had the sheath for a month or more and some are just starting to show signs of bud formation and expantion. So dont give up on them just they just might need some more time.
Remember that plants like skinneri have in-essence a blank looking sheath that usually dries up in the fall and looks dead. Then in the spring....like magic 3 to 5 buds emerge.
Cathy--that's good info, thanks. I always wondered if that phenomenon was linked to a particular species in the background.
The presence of a sheath does not necessarily mean that buds will form in it. Occasionally you’re lucky enough to own an orchid that will bloom from every new sheath and sometimes even from every new psuedobulb. Some cattleyas only bloom on the last psuedobulb even if sheaths formed on the previous ones. If buds are going to form at all, it can be several months after the sheath formed. On some orchids all the buds start forming at approximately the same time. Others may be sequential bloomers where one sheath will form buds and bloom and then weeks later another sheath will do the same. It’s not a good idea to disturb the sheaths because you never know which ones may form buds. To further confuse things, buds can form on psuedobulbs that do not have sheaths.
I also have plants that get a sheath within a sheath (just to make things even more fun...). I have a couple cattleya that only bloom once a year, at the same time every year. So, if it grows three new leads and sheaths, they just sit there until it's time to bloom and then one or more of the new growths can bloom. Visitors don't understand why I don't have tons of plants in bloom all the time. When I tell them some only bloom for a few days a year they look at me like i'm nuts.

Usually the larger standard size catts (both bifoliate & unifoliate) produce sheaths. They can sit there for a couple of months before buds emerge from within. And sometimes they just sit there and no buds grow if they do not receive the proper stimulus, usually reduction in daylength, for species like mossiae and labiata (I think). Mini catts without sheaths are easier, as there is no risk of buds rotting in sheath, such as some Potinaras, cattleytonia, and those with brassavola influence.
I really like this information it is very informative, as I have several cats and have not have any blooms yet but i have a big catt that has now 5 sheaths but no bloom yet. i can't wait. thanks for the info.