Beginners do best with bark or coconut. Water once a week and you'll be fine Sphagnum Moss works also but the watering has to be very precise. If you soak it once a week, the plants will be way to wet This is fine for some of the 'cloud forest plants' that get rained on every day but not for the Oncidium you showed a picture off. The Miltionopsis is difficult at best, probably won't rebloom no mater what you do unless you get lucky.

I use Sphagnum moss extensively but recommend to beginners to cut their teeth with bark.

Nick

Yes, I agree with the thing about Sphagnum Moss, it is a valuable potting tool but watering is tricky. The Oncidiinae Sub- Tribe covers many orchid Genera and Species, so you need fine tuning for the many types.
The Canadian Orchid Congress has some good culture notes on its Web-site.

I don't use a lot of sphagnum moss because I am heavy handed on watering. I use it on mounts between the plant and substrate.
There are many successful methods. Each grower will find what works for them. I use various types of mediums. The one I use the most is lava rock. It does not hold a lot of water which gives it a chance to dry before I show up with another douse by the hose.
Use this thought to manage your watering. Orchids must get wet and dry somewhat by the next watering. A general statement. There are exceptions.

Thank you very much for all your advice. So, should I take them all out and mix with husks or lava rock or barks and put them back in the same pot? Would I give the shock because I just repotted them only about a month ago? Please help. I see some new healthy shoot from some of them but as you said Nick, the Miltoniopsis is stand still and the young leaves are accordion like though the moss are still pretty moist.
Thank you!

What are your growing conditions? It is hard to suggest growing help when we have no idea where you live or the environment you are growing your plants. What is your light, temps, inside growing or outside?

This is not the time to repot. Spring is when repotting should be done when plants are making new growths and roots. They can handle root damage better and are growing in better conditions. Longer days, more light and warmth.

Without growing information, I would suggest leaving them alone, make sure you do not overwater and carry them through the winter. Repot in Spring with small bark and some perlite, again depending on your environment. Sphag could be used mixed with bark.

I agree with Orchidnick, these plants are tricky to grow and very sensitive to overwatering and dry air. I never had luck with them over the long haul. I was growing in zone 5-6.

Jane

I'm not against SM I use it and it works well. As long as you don't over water, your plants will be fine. If they appear to go downhill, pull them out of the pot and inspect the roots. If the roots are mushy and unhealthy, repot in bark no matter when.

Nick

Thank you Jane and Nick. Jane, I live in Alberta Canada. This time of the year is quite cold but all my orchids are in door. I have a few Phals which like warm and some others such as Miltoniopsis and Intergeneric kinds which like cool. I am trying my best. I have them all on a table by the west facing window, closest to the window are Phals and a bit further in are mil. and Inter. I mist them may by every other day with fine mist. I hope I'm doing it right. If you and any one who know much about orchids can pass on any advice I truly appreciated.

Tanie

I grew up in Calgary, -40C for 4 straight weeks in January should represent no problem!!!!!! Went to university in Edmonton before moving to sunny Southern California. Built my mother a full greenhouse inher basement. She was very active in the Foothills Orchid Society

I know exactly what you are up against. I'm dealing with 'Santa Ana' conditions right now which gave me 95F in the backyard today and should produce some spectacular wildfires.

Nick

I contacted Paramount Orchids and they gave me this website. Thanks to them otherwise, I spent all day looking and searching. I am glad I found this website. You all have been helpful. Thank you! Well, Lethbridge is in Fall and it is very beautiful right now with all the colors leaves, red, orange, yellow and purple.The weather is getting cooler and cooler.... I keep my living room pretty cool. (65F) for miltoniopsis and oncidium and that kinds. I brought my Phals to another room which facing east and it's warmer and has some sun shines in about 1/2 hr. in the morning. I hope I am doing the right thing for my orchids.

You don't need to repot them now. Its a bad time of the year to do that. If everything is alive, leave them alone. The mix you are using sounds fine.

Good luck,
Jane