Dendrobium cretaceum Care in Winter

[wenshen]

I am new to the orchid world. Last May I bought a Phalaenopsis which I didn’t except it would survive after blooming. One day I heard from a friend that Phalaenopsis is easy to care and rebloom then I decided to give it a try. When I saw the new leaves and roots growing I was so excited. I started ordering more orchids and learning how to take care of them. I love orchid board, I learned so much since I found it. Just wish there is a phone App so I can read it easier from phone.

I bought a Dendrobium cretaceum last Fall, bloom size. It’s in my walkout basement close to east-facing window. There was no sign of leave dropoff the whole winter. I didn’t cut the water (once a week) until recently I realized it need to be dry and in lower temperature at night in the Winter. So I moved it to the windowsill one week ago. Yesterday I noticed the top leaves turned yellow, is it a good sign that the plant switched to deciduous mode or is it too stressed it doesn’t like to be a cooler place suddenly?

The first two pictures are the Dendrobium cretaceum which I am questioning on. The last picture is the phalaenopsis I got last May and is reblooming now!

Wen

[Roberta]

First, Welcome! And congratulations on reblooming that lovely Phalaenopsis!

As far as the Dendrobium is concerned, drying will make leaves tend to drop... normal for this type of Dendrobium. The time to start drying, and cooling these actually is much earlier... like November/December. We're getting pretty close to the time for new growth now. So I'd suggest light watering. Also, it's a small, young plant. So at this point, I think leave it where it is, but your weekly watering is about right. If it didn't get the drying and cooling, the worst that happens is no flowers... if treated too aggressively, it can be fatal. Early in my own "orchid-growing career" I received the advice on nobile-type Denbdrobiums (similar needs to yours) to give no water from Halloween to Valentine's Day .... I killed several before I figured out that the treatment was too harsh. So I water less in winter, but do still water some. (In nature, they may get no rain in winter but they get humidity and morning dew. They don't get the single-digit humidity that happens at my house occasionally during the winter...)

[wenshen]

Thank you Roberta! I will leave as it is and keep watering once a week.

[estación seca]

Welcome to the Orchid Board!

Yes, in orded to flower, winter cool nights are more important than drying out for this kind of Dendrobium.

[Orchidtinkerer]

welcome wenshen,
some excellent advice from Roberta.
As I have recently mentioned I go so far as to never let any one of my dendrobiums dry out. I have like 25, nobiles are some of my heaviest drinkers.
The drying out thing is a backyard myth if you ask me!
They need cool winters and in cooler conditions they drink less and rot easier so keeping them drier makes sense to avoid the roots rooting which is not good but never go so far as to purposefully dry dendrobiums till the canes wrinkle, it does not benefit them in the slightest.

ps: If you ask me the yellow leafs are from too little water, it will be fine if you just increase the watering. If you make a dendrobium lose all it's leaves you could be in trouble although they are tough and can usually still produce a new cane the following year.

[Roberta]

One more note... Many Dendrobiums bloom from old, leafless canes. So don't ever cut them until they are totally brown and shriveled (and even then, maybe wait a year to make sure they're really done) It is truly amazing to see flowers emerge from an old cane that looks quite dead! Also, once new growth starts, increase the watering and start fertilizing lightly (Dens tend to be very light feeders)