Coelogyne dayana outside in zone 10?

[orchidsarefun]

most people want to grow a specimen-sized orchid that would be described as "stunning". You may succeed in growing your dayana under your local conditions, but it would be heartbreaking to have a magnificent plant killed off by a prolonged cold spell. As your temps already go to 0 on occasion, the likelihood of this happening increases.

Another suggestion - in my garden I can tell where the cold/frost "pools" ( low-lying areas ) and which areas over the longer term don't get as cold. Are you able to do the same ? For example mounting your plant on the opposite side of a tree trunk may be perfect to protect it from cold winds or mist/fog etc.
Another example - I can grow vegetables against a south facing wall far earlier than "normal". I am doing so now. The wall radiates heat and keeps the soil at a minimum temp.

[Kostas]

Thank you very much for your replies both of you

Plants can easily thrive and many species do thrive in places with temperature ranges much outside their optimal range. For example,Cycas multipinnata and Castanospermum australe(and many others) thrive in my garden seeing a temperature range much outside their optimal and the one they see in habitat. Most plants dont need optimal temperatures year round to thrive,they just need them for at least a certain amount of time to put on good growth and get ready to face the difficulties again. They will certainly grow faster if kept within their optimal range but they thrive just as well seeing temperatures outside of it(within a certain limit of course)and just grow a little slower. The tolerance of plants of temperatures outside their optimal range varies a lot from species to species and especially genus to genus. So,i cannot make a generalization for this particular species and say it will live in my conditions but i can say that if it withstands that cold,it will certainly thrive and grow into a huge specimen in my condition,much bigger than it would ever get in any pot.

About why i have my orchids so far away,its simply because i dont have the space or the suitable climate to grow them where i live. When i get a big piece of land for a main house someday,in an area with almost equally good climate as Pyrgos,i will grow orchids there as well on trees and get to enjoy them everyday then. But even now that my orchids and other tropical plants are so far away,i must say i enjoy them more than if i grew them potted at my main house as i get to see them grow and flourish to their full potential in a climate that is very close to their liking or even perfectly to the liking of some I get to grow huge growing trees and palms and all kinds of beautiful tropical plants in a rainforest scheme where all kinds of plant groups are growing together and forming the mosaic of plant life seen in the rainforest. Well,i dont see any other way i could enjoy this beauty on weekends and on vacations so easily as i do now,just driving 300km in just 2,5hours and instantly enjoying a tropical landscape! Also,i get to enjoy seeing my orchids grow in their natural way,on trees,and in time,i will get to see them form huge specimen on the tree trunks and attain sizes only a huge amount of pseudobulbs and unrestricted growth can allow!
In addition to all the above,i dont need to provide any care for them other than the auto-irrigation system which keeps them moist and happy! No hand watering,no fertilizers,no repotting/re-mountings,etc. I just go there and enjoy the view along with adding more!


Pyrgos never gets prolonged cold spells as the cold is always the result of heat loss to the sky and not cold weather coming all the way down to Pyrgos. That doesnt happen. So,it does might get a little lower than -2,5C but the briefness of the cold temperatures is the same. For this reason,my microclimates provide excellent protection to more sensitive plants.
Yes,i do have located my microclimate and now know which is good and which bad. I plan on growing this and other more tropical species in my best microclimate,in a tree between 2 walls(thats where i have my other orchids mounted as well),so they get the best protection but i dont know how much difference in temperature it makes. I only know damage is much less there,always!
I know what you are saying about the South facing walls and do use the south facing side of the trunk to my orchid's advantage,especially the ones liking to get some sun as well. I guess it helps them at least grow faster thanks to the increased light levels and extra heat

However,even though selecting a good mounting location will help give this orchid the best chance,it still has to be able to take such temperatures for it to survive. I cannot know its cold tolerance without anyone having tried it. That leaves me 3 options:try it and see how it does next year,wait till someone tries it or go with Coelogyne tomentosa(C. massangeana) which is reputed to be more cold tolerant and listed as zone 9 instead of 10. Does Coelogyne tomentosa get as huge as Coelogyne dayana(C. pulverula)? Does it get leafs 80cm long and equally huge pendant inflorescences?


Thank you very much in advance!

[camille1585]

Sounds like you need to move there!! Must be a beautiful place.
That reminds me that I said that I would look up Phals in your other thread.

[Bud]

If the plants are well established then it might withstand a brief spell of cold...if it is a seedling then it will need all the help to survive.
Two weeks before the cold spell comes you want to wrap the roots of the mounted plants with plastic bubbles or some cheap materials that holds heat...you just have to travel kilometers to do this...
like most of our grape growers in California ...when the frost comes they know of homemade remedies to help the plants survive...
youre lucky that you will do it only once a year...or maybe not if that year will not have frost at all

[Kostas]

Thank you very much for your replies!

Yeap,Pyrgos is a wonderful place and i would love to move there!!! It requires a lot of changes though and i dont know and to find a job there and thats whats keeping me from moving for the time being...Otherwise,i am sure i would be much happier living there and i would have lots more free time than i do here. Life is slower there!


I understand that difference Bud and i have easy access to adult plants of both species so that wouldnt be an issue. Covering the roots in advance of a cold night is very difficult as there are no cold spells in Pyrgos,is only 1-2 individual nights spread out through the winter that may get to 0C or a little below it and they are not easily predicted with accuracy. Also,it would be very unhealthy for the orchids to cover them or their roots 2 weeks in advance as in Pyrgos it can get to 18C during the day easily every month of the winter and that would heat up the covered areas too much and too fast. I would think this would make things worse. This winter has been pretty bad for Pyrgos and i got no damage on my orchids(except the more exposed Lycaste lasioglossa with 50% leaf damage)with no added protection. I would like the Coelogyne i choose to also withstand the winter lows with no protection and no damage.
Grapes are grown all over Pyrgos's suburbs and always unprotected. They never get any damage here and nobody bothers to protect.


Searching more on C. dayana(=C. pulverula),i found that its supposed to be less cold hardy than C. tomentosa(syn. C. massangeana) and that C. tomentosa is considered reliably hardy in coastal Callifornia and taking a couple of degrees of frost unbothered. So,i would think that C. tomentosa should also be reliably hardy to Pyrgos. I havent found any cold hardiness info on C. pulverua unfortunately but i did find a mention that a C. pulverula passed the summer outdoors in northern Europe,seeing 5C as night temperatures and it grew unbothered though slower and even flowered!!! Here is the link:
Coelogyne dayana [Archive] - Slippertalk Orchid Forum- The best slipper orchid forum for paph, phrag and other lady slipper orchid discussion!

This is the only mention of a C. pulverula doing so well down to 5C and the only somewhat promissing info i found on this species. Reading this experience,would you think it would be hardy enough to see 0C to -1C or a little more and remain undamaged or would that be pushing it too much? Have you heard of or have yourself experience with growing this species down to 0C?

Does C. tomentosa(syn. C. massangeana) get as huge leaf size and general size as C. pulverula(syn. C. dayana)?
Do you have any experience with C. tomentosa outside,unprotected in zone 10 or in temperatures down to 0C or -1C to -2C?

Thank you very much in advance!