Plunge temperature for orchids

[Tony Willis]

Mark

I have seen this sometimes on both ophrys and orchis,different plants,different years. It may be virus and if it is does not seem a problem but I have always put it down to stress,both mine and the plants. We do not provide optimum growing conditions and yet expect them to perform.

Keep the aphids away just in case but otherwise I would ignore it.

[Anthony Darby]

I agree, although my experience is much more limited. I would be delighted to see such good growth and would misquote Nelson: "I see no virus".

[krisderaeymaeker]

Interesting topic ! I grow my Ophrys and Orchis in my greenhouse . I keep it just frostfree because I grow my cacti in the same enviroment...
Just a few pictures from my collection ...   

[Tony Willis]

my first ophrys is now open - -Ophrys lutea

[mark smyth]

Looking great Kris.

Mine are developing fast which is probably down to the double figure temps we had for about a week

[krisderaeymaeker]

Looking great Kris.
Mine are developing fast which is probably down to the double figure temps wer has for about a week

Thanks Mark , you're right ...they are really fast now! The first signs of flowers showed up in one week.
But here we expected some wintercold for the weekend.... 

[SteveC2]

O.K. so the temperatures are higher than normal, but the light is minimal, maximum eight hours daylight, mostly overcast.  Can't say that I'm seeing any real signs of accelerated growth.  Are you using lights or is the west of the U.K. actually seeing the sun?  Actually I think Kris in Belgium might be closer to me than Mark!  Have you actually got sun?

[mark smyth]

no lights and yes it been over cast most of the winter with only a day or two bright sunshine. At this time of year my green house only gets direct sun, when it shines, for the last hour. In a few weeks morning sun will shine on the green house again

[mark smyth]

One of my Anacamptis morio is looking sick. Close inspection shows a small colony of aphids. They will be sorted when Homebase opens. I suppose I should treat all plants while I'm at it

[Tony Willis]

Keep the aphids away just in case but otherwise I would ignore it.

You should have sprayed as a precaution and now definitely need to get on top of it.

[Tony Willis]

I have recorded the air temperature in my greenhouse and the air temperature above my plants in their insulated box at soil level.

These were -4c in the greenhouse and +4c in the box. The soil warming cable has not been activated and that is set at +5c  five cms below the sand surface. At the moment the ophrys look fine and many are sending up flower shoots.

[mark smyth]

-16C forecast for tonight in the midlands

I checked various temperatures just now 7pm
air 4C
soil 1.2C
unheated plunge 2.6C
heated, gasp, 6C. I'll check it again in the morning after turning it down until the thermostat clicked off.