http://orchidlady.com/pages/orchidGarden/orchidCare_3.html

DEAL TEMPERATURES FOR ORCHIDS
COOL
Max. Day 80 oF (27 oC)
Min. Night 50 oF (10 oC)
Cymbidium
Masdevallia
Miltonia
Odontoglossum
Oncidium
Paphiopedilum

INTERMEDIATE
Max. Day 85 oF (30 oC)
Min. Night 55 oF (13 oC)
Oncidium
Cattleya
Dendrobium
Laelia
Paphiopedilum
(mottled leaves)

WARM
Max. Day 90 oF (32 oC)
Min. Night 60 oF (15 oC)
Phalaenopsis
Vanda

Your dendrobiums should already be in at those temps. While they can survive lower temps, they are not going to grow and bloom well if chilled. (I am assuming you are speaking about hybrid Dens. Species Dens are a whole different matter)

As for your Catt, it depends on what the parentage is as to when they have to come in. If they have a lot of C. aclandiae or other hot growing Catt species in them, for example, then they also need to come in right now. Hybrids with a lot of L. purpurata in them can stay out until temps drop into the upper 30s.

Oncidiums tend to do well down into the 40s at night as long as they warm up during the day.

There are exceptions to every rule; sometimes it is much more subjective and depends on the indiviual plant and its makeup. I have some Phal species which stay out down to 32F, which would kill my hybrid Phals.

If the dendrobiums are nobiles, they need 25 days of 50 or below in order to bloom well. For me that's usually early November. Check the Yamamoto site for his culture recommendations.

As to the rest of the advice you've received from Houstontexas123 and CJ Watson, it's spot on.

Funny you mention that about your species phals, CJ. I was going to say basically the same thing, except I do that to ALL of my plants (even hybrid phals!). At the moment, its catts, phals, and random assortment of species. They all stay out until the night of the first expected frost. I've noticed a lot of the plants seem to basically do well with this treatment. Phals have definitely bloomed better and growth has overall been a bit stronger. I haven't had any problems arise as a result of this.

I also do this because I dont want to play the in/out game, where plants are moved inside one night then back outside the next warmer day, be it moving the whole collection or certain plants that may or may not like it that cold. I certainly wouldn't do this with vandas, but the plants I DO have fair well with this system.

For the rest of the phal growing world, you might not be as lucky as terpguy leaving your phals out below 45 degrees. If subjected to that temp for several hours, you will begin to get some cell damage. Below 40, and it can be serious damage.

Terpguy must live in a wonderous micro climate to permit phals to not suffer serious damage below 40 degrees. They give you the low temp recommendations so you can grow your phals at their best.

As cj says, there are a few species phals that take low temps but they go deciduous and must be very, very dry or even they suffer some damage. If kept in a warmer environment, the deciduous phals won't lose their leaves. Keeping the leaves on the deciduous phals will make even them grow and bloom better.

Brooke

My Phals never go outside! It is a hard cruel world out there. Problem solved!

Those cool, intermediate and warm thingos are just a guide and lots of fine tuning is required.

No one grows Cymbidiums inside here and towards the western parts of the city away from the Pacific Ocean night time temps regularly get down to 40F and lower.

The other thing that has to be taken into account is hours of sunshine. Cool nights followed by sunny days are not as bad as cool nights followed by many gray cold days.

I admit to doing the same as terpguy. All phals have been moved in last week, everything else is still out. I'll move my warm growers in this weekend if it stays cool. Dens stay out, even the hybrids.

The sun is strong during the day and most of my Catts seem to perk up with the cool nights. All Oncids and most intergens stay out till Oct. Too cool at night for Phals.

Many of my plants are old and have always been treated this way without a problem. Only thing to watch for is too much rain and cool temps. But with common sense, most plants seem to like the cool, sunny weather.

Jane

LOL No wonderful microclimate, just a balcony in a garden-style apartmnet :) *dreams of a greenhouse with too many microclimates to count* I do agree with you though, Brooke. Its a calculated risk, the consequences of which I'm painfully familiar (like everyone else, I've lost plants to cold damage). Its not for the faint of heart. I will say I don't have any species phals, I seem to kill every single one of those I've ever tried before they even get to winter. But for the phals at least (funny we're focusing so intently on these, I only have 3 of the little buggers), as a result of this, they HAVE started blooming better than before.

Funny story: I was talking to a nurseryman at the maryland orchid show and sale earlier this year--cant for the life of me remember who it was--and was telling him how far all my plants get down in temps, and without telling him the results, his very first question was "have you noticed better blooming?", his tone suggesting the answer was supposed to be yes.

Chris, be careful with your Phals!
If your balcony has a roof over it and is not open to the north wind, it can easily be 5-10 degrees warmer than the outside temperature. A roofed-over growing area, under a leafed tree, against a south-facing wall, over a concrete/brick patio are all useful microclimates. Never go by the weatherman's numbers, your yard can be warmer or colder; know the temperatures differences in various locations.

Very keen, CJ! All the places I've done this (and its been a few), they all were some form of sheltered south facing lcations: either sheltered by trees or recessed balconies. Not by design, mind you. Its just what I had available.

I'm not worried :) Like I said, I'm aware its a calculated risk (and not for everyone to try!). Frankly, I think a small part of me is hoping for them to die so I can make some room for a variegated Stephanotis floribunda or Gardenia coronata. *devil horns*

Ah, so deep inside your little bitty heart, you are somewhat of an evil herbicider, Chris? Hmmm.

Back to Vandas, there are several species which grow in high mountain areas which like cool weather (down into the 40s) and whither away and croak if subjected to long hot summers; Vanda coerulea comes to mind first.

"I dont want to play the in/out game, where plants are moved inside one night then back outside the next warmer day, be it moving the whole collection or certain plants that may or may not like it that cold"

Well,that's certainly how I felt last year. So a cold wet spell early in September brought all the phals in for the "winter". But that cold wet spell was followed by more than two weeks of glorious warm weather.

Night (day as well) temperatures are extremely variable here this time of year. A night of 58 can be followed by a night of 72.

The solution, for anyone who wants to try it, is to put the orchids on biggish two-shelf carts. These hold a lot of plants, and can be wheeled in or out in about 5 minutes. You can have one cart for "warmer" and one for "cooler", and then might only need to bring in one cart.

The carts also enable me to protect them from bad storms or several days of cold/dim/wet which we get every year. Shade cloth is easy to rig, supported by the carts themselves.

This spring I found that in direct sun, temperatures on the cart are at least 70-80 even if the ambient temperature is 55 or so. So being outside on sunny days, not only gives them glorious sun, but also much more warmth than they would get indoors.

Using the carts this spring, I was able to have phals outdoors from the end of March and got wonderful growth and spikes on every mature phal, over 20 of them spiking. By April, they needed shade cloth!

This fall, based on last year's weather they should be able to be outside most days til at least the middle or end of October, maybe even later.

An example: yesterday and today were warm and humid-- temperature in the 80's, nights in the 70's. Tomorrow we get up to 6" of rain from Ike, some quite heavy, and they will come in tonight and stay in til Monday morning, when the rain will be over and the sun bright again, but the day cool. In Monday night for the low of 50F, out Tuesday, etc.

It may seem like a lot of trouble, but it takes no more time than filling a couple of glasses with ice to take to my desk, and it shortens the winter here by about 4 months. And to me, THAT is priceless.

My only problem with orchids are the long, long winters. If you grow indoors til nights reliably above 60 in Spring (end of May) and from same in Fall (early Sept), the "winter" is 8 months long. Too long. By Feb, I can barely stand the mess and clutter one more second.

The carts shorten the winter to 4-5 months, a little over half. And that's worth 10' a day to me move the carts in and ouf for a few months.

Hope this can be of use to someone, since it took me 5 years to evolve this solution. (Yes, sometimes I'm pretty slow)

Thank you all for your insight on my question. Once again it seems to come down to culture, knowing exactly what plant you have, and the requirements of the plant. This past summer I put all of my orchids outside. Even though the plants were in shade under deciduous tree, I had some issues with burned leaves. The burned plants I brought back inside the house. I have had mostly positive results with the plants that remained outside. I think next year I will put all of my orchids outside and for the sunlight intolerant I'll provide additional shade with a wire or cloth barrier. Moving forward I am going to work at providing more light to my plants, providing constant air movement, flushing the root systems when I water, and supplementing my orchids with a mild fertilizer.

Sounds like an excellent plan, quicksilver. I am sure your orchids will appreciate it and thrive.

I'm curious, mehitabel, about your carts. Could you post a picture, please? I'm wondering, too, where you put them outside and what you do with them inside? Since they are "double-decker" how do the ones on the bottom get enuf light? I could do it with a couple wagons but have no place to put them inside except under a table so they wouldn't have much light when inside. Would you mind telling us more about your carts? Thanx, Barbara.