Observations on Vanda dormancy...
 

Windowsill grower here...

I have a NOID vanda in a vase in our bathroom which faces west. Lots of sun and the vanda thrived. Come wintertimes, the bathroom gets very cold. Vanda was ok for a month or so, then slowly her roots would stay green for longer and longer periods. Dormancy?

Being a newb, it took me a while to figure out it was too cold for her and put her in the warm south facing room. It's been a week and her roots are still green. Will water her when the roots turn white.

Now, take a cosmic mind leap to neofinetia's need for a cool, dry rest. Could it be that the cold could slow down the neos metabolism so they don't need as much water?

Will never say that vandas and neos are the same. But then, evolution started with a single cell.

So right now, vanda is in a warmer place and my little tribe of neos are in a sunny, cold bathtub.

Any thoughts on the subject?

I have read that, once Vandas go dormant due to cold temperatures, it can take weeks for them to grow again. I try to keep mine above 60F / 15C and they keep growing. I seem to recall others here try to keep them above 50F / 10C. I have read they start dropping leaves under 45 F / 5C.

Depends on the Vanda. V. tricolor, V. cristata, V. roeblingiana don't seem to mind the cold, V. coerulea doesn't do much, but it doesn't die either. I cut back water for everything, which seems to help. Hybrids with Neof. falcata (Neosytylis, Ascofinetia, etc) are very cold tolerant. The bigger hybrids are another story - most of them have varying amounts of V. sanderiana in them, making them want temps more like Phals.

Just don't let your Vandas go under 50F. They will not go dormant=they will start to die. Vandas need warmth and sunlight. Do not wait for the roots to turn white....soak them in lukewarm water and you will see the difference. Cold is its enemy. It might also get bacteria and fungi infestation. Overnight is enough to let the roots dry out. Vanda has high humidity in situ and your zone 9a is right for Vanda culture=just don't let it feel the frost.

---------- Post added at 02:10 AM ---------- Previous post was at 02:05 AM ----------

I have seen Neos in Japan growing on trees in the snow. But the thermal heat of the living tree must protect its roots. And the snow just melts in the day sun. But do not let it happen to your Neofinetia since most of the US bought plants are grown in labs. The US Neos are pampered and given the correct temperature and humidity. So treat it as such....pampered.

Don't tell my Neos... they don't get snow, but do get night temps in the 30's F and thrive. They're tough... But they have also acclimated. This isn't a good time of year to be moving pampered greenhouse-grown plants into harsher conditions. Wait for spring before even thinking about it.

Observations on Vanda dormancy...
 

Neofinetia are different with respect to temperature and water requirements of other Vanda. The geographic distribution offers information on their culture. I think Neofinetia are Vanda that adapted to their environment.

Neofinetias are highly adaptable plants to YOUR conditions.

If you grow warm in winter (good light and above 18C nights) treat them as in spring/summer. Water when dry. This is esp under lights, where they grow constantly, therefore needing water and nutrients (very light feeding).

If you grow with cold nights (below 15C nights), treat as winter rest time. Water when crispy dry or they will rot (unless there constant air circulation).

I always water base on plant performance. They tell me what to do. If roots start, it's time to increase water/fertilizer. This happens in late winter for some.

So no matter what time of year and lighting, the plant will tell you what it needs. Yes, it's good to 'force' a winter cool rest for better health and blooming, but not necessary. I have bloom plants well even without winter rest.

For Vandas, each species has it's needs of cool nights or not. If it has the background of warm night requirements (most round hybrids like Ascocendas), it will sulk in cold. But if it has cold species like coerulea, it will thrive with cool nights in winter.

I have roots of vandas stick in vases that had cold water for days. All fine but I drain out water once a week. Keeps water fresh and warms them up with new room T water.

This is my experience. Hope I haven't confused anyone :)


Sent from my iPhone using Tapatalk

This is very interesting.
Since last August I put together a small collection of Vandaceae.
Apart from two Darwinara they are all seedlings deflasked last August.
These days are the coldest of the year and the night temperatures are just above 60 F.
Also I have noticed that the roots tend to stay green, so I decreased the frequency of watering.
But I noticed that although very slowly there are signs of growth.
Particularly darwinara started spiking and neofinetia produced new growth.
Vanda and Rhynchostylis show modest growth of new leaves.
Best wishes to you and your plants
ciao Nicola

For WARM GROWING Vandas, the lower limit is 55F at night. Below that treshold, they go into dormancy and sulk for months.

For COOLER GROWING Vandas (tricolor, etc.), you can go a bit lower, and cristata is even more tolerant.

In the northern part of it's range, Neofinetia falcata is exposed to snow and a touch of frost.

Common for all Vandas, during the colder & darker months, you should scale back watering & fertilizer - but do not stop watering.

Just figured out the bathroom is around 65 F right now. Probably gets colder at night, which are around the same temps you are giving.

From now on when it gets cold in there, Vanda goes in the warmer south room.

---------- Post added at 12:33 PM ---------- Previous post was at 12:22 PM ----------

Have RO water warming up right now. Going to put some Physan 20 in the water too for good measure.

The neos are my babies. Most of them don't mind a dry, cold period. Just not too dry and not too cold.

---------- Post added at 12:47 PM ---------- Previous post was at 12:33 PM ----------

No snow for my Neos either. Mine are windowsill grown where the house temp right now is 73 F. I've moved them into the bathroom where the temps are 60 - 65F. Not that much of a difference.

Think your Neos are tough too!