Do any of you have recommendations for orchids that might like my new greenhouse conditions? This is located at 6500 foot elevation in Arenas Valley, NM. I am keeping it at 55 degrees F in winter, and in summer it can go to about 103F with all vents open and a solar fan going.

The greenhouse does have shade cloth over it in summer. It has a 700 gallon water tank "pond" with water plants, fish and a small solar waterfall. The humidity varies a lot. During the summer it is about 30% in the daytime, and goes up to maybe 70% at night. Right now it's been raining and snowing, so it's running about 70% during the daytime.At night it's dipping down to about 25% humidity.

There are no trees tall enough to hang orchids. If I did, the deer would have a feast! I do have a second story deck, and I could hang plants during the summer under the decking where we have chairs and a small fountain.The under deck area gets morning sun.

I could also take any orchids inside my sunroom in the house if the winter temps are too cold.

That's a pretty tough temperature range and so far I'm just experimenting to see what does well in there. I don't have any orchids, and only a small amount of orchid experience. Please try to keep it to orchids that are considered good for beginners.

Karen, my first thought (seeing NM and AZ as your location) is "not enough humidity". You're going to struggle with orchids there especially in the summer. The high altitude will also be a difficulty, since your thin air makes the sun more intense, and the air is also less able to hold moisture.

Your greenhouse will be great for the cooler months, but most orchids can't take temperatures above about the mid-90's and really want high humidity. I think you might find yourself schlepping your entire inventory of orchids into your sunroom for the summer months just to keep them alive. Then you'd be babysitting them to keep the humidity up in your (presumably air-conditioned) house. No way they'd survive being outdoors in your dry environment unless you tended them constantly or set up an automatic mist system.

Hmm, speaking of mist systems, do you have a swamp cooler for your greenhouse? They work great for cooling and moving air in dry climates.

My daughter lives in Utah, and has been wanting to try growing an orchid for years. I recently bought her an Oncidium 'Sharry Baby' at Trader Joe's (their prices are reasonable) that so far (6mo. or so) has done fine living in her bathroom which is for sure the highest humidity room in the house. They both shower daily, and she mists the plant fairly often, too.

All those Phalaenopsis (aka Moth Orchids) that you see for sale at the big box stores are really not well suited for your purposes, and in fact I don't think they're particularly easy orchids for beginners even though they are sold as such. They need indirect light and moderate temperatures, neither of which you're going to find easy to supply. Go for orchids that can tolerate very bright light and don't mind drying out somewhat - Cattleyas come to mind.

Thank you, Elaine. I appreciate your thoughts and expertise. Humidity is definitely a problem. The bathroom is a possibility if we were there all the time. Unfortunately we travel back and forth and usually I'm away from NM for at least a week or two. I'd have to set up lights and a watering system in there.

The greenhouse is set up to do everything automatically. We have no swamp cooler. It's just a small 15 foot dome. We did set up a mister system, but our well water is too hard and after having it mist just a few times, my plants all had a white coating on them. Really ugly! I don't use the mister now. We got a filter for it, but it didn't solve the problem.

It sounds like orchids may not be practical. You mentioned Cattleyas and I remember seeing them living outdoors when we lived in the Marshall Islands. They seemed to always be in bloom, and very happy. Of course, the humidity there was very high all the time.

Karen, a swamp-cooler would be of great value to you. Can you tell me the configuration of your greenhouse? I don't quite know that a 15' dome is. Regardless, that make swamp-coolers in all sizes and they are pretty inexpensive. All you need is a water source and a 120V outlet. That would not only greatly increase your day-time humidity but also move air, an important element when growing tropical plants. Could you take a picture of how the deck looks, at least showing the bottom aspect when plants might hang. That's a real possibility there and an automatic watering system could be set up under the deck that would not only water the plants but also raise the humidity. Morning sun is the best sun!

Not only are most of the cattleya a good choice but Vanda are surely a good choice too. Dendrobiums by and large, tolerate heat well, at least for me here in NE Mississippi. Our average high here from June through September is easily 90F (especially July and August) and it is not unusual to have weeks and weeks around 95F. We often see temperatures at or above 100F as well. But the one thing I have that you don't is pretty much constant high humidity.

Karen,
I had a greenhouse in NC with an inch of gravel everywhere except for cement pavers down the path. That really helped retain humidity and if you had a swamp cooler I think you would be all set. I grow mostly Catt's and they are quite flexible..my night time temperature was set for 60 during the winter and sometimes in the early spring it would get pretty warm ... I had a few over 100 degree afternoons in a row and the plants didn't complain (much)!

Gravel works, but for me I use cypress mulch (4" deep), overlaid with greenhouse fabric. I think the cypress holds and evaporates water for a much longer period.

Karen, I have a similar situation , though at a much lower elevation. The orchids that do best for me are Ansellia Africana, Epidrendrum Radicans, Epi. Secundrum, Sobralia, and some of the Mexican Laelias, plus Zygopetalums. These live outside year round here, and will take temps down to the freezing ( for short periods) with no problem. These are not the big, floofy flowers though. As I see it, the hard water is the big issue. Ours is pretty bad too, so rain barrels are my solution. I have no way of pumping it, so do my watering with a 1 gal. pump sprayer. I keep a fan running in my tiny greenhouse, and if It is closed up, that helps keep the humidity up a bit, and the temps up also. I'm testing a Vanda in the greenhouse, but I think they need a lot more humidity than I can give them, and as with all orchids with exposed roots, they need daily watering. Phals have to be house plants here, where I do have a swamp cooler on my mobile home. It keeps the temps down and the humidity up. Some of the Cattleya hybrids survive in the greenhouse, but don't thrive for me, as a rule.
Hope this helps a little.

Ken, don't forget when your orchids are outdoors in the summer, they are under your oak trees which keep things much cooler for them. Even on a day touching 100deg. it's probably only 92 or so under the oaks.

I wouldn't give up the idea altogether, at least until you try a couple of orchids for a while. Go for some that Carol recommended - the Mexican Laelias sound like a good idea - and don't buy show plants in bloom! Get some relatively inexpensive ones so you don't break the bank on your experiment and give it a try.

In my experience, the orchids I've spent the most money on are the first ones to die off for me. Younger orchids maybe a year from blooming might acclimate to your conditions better than a big plant, too.

Yep, I know that, Elaine, and have posted several times about that very fact. Heck, on really, really hot days, when the temps are above 100F, you can actually stand under those trees and feel a mist falling from those leaves transpiring.

Thank you for all of the help! Ken, I think I could put in a very tiny swamp cooler. We do have water and power.My greenhouse is a Growing dome that is just 15ft in diameter with planting beds all around and open space in the center right now. I can hang plants, but there isn't as much space as a normal glass house since it's a geodesic dome shape. Here is the company:
http://geodesic-greenhouse-kit...
I don't have much time today, but I will get picks of the deck. I hadn't thought about putting the water there, but that is a great idea! I'd probably have to fence it off because we have had the deer come right up to drink from the fountain. They'd love an orchid feast.
I appreciate the plant lists and your other experiences. I really hope this can be worked out.

I would love to know more about your set up, Karen. You talk about a small dome, but you also mention a decent size pond with Fish and Waterfall. This 700 Gallon tank should provide some decent conditions, provided there is still room around or above it. I have a hard time picturing your set up, am I missing something here?
I keep trays underneath my Orchid shelves to keep up the humidity, you have a whole pond!!

Karen, we cross posted!

drdawg said:

Gravel works, but for me I use cypress mulch (4" deep), overlaid with greenhouse fabric. I think the cypress holds and evaporates water for a much longer period.

I forgot to say that the floor right now is hardware cloth to keep out burrowing critters, covered with pea gravel and I have square pavers over that. Haven't finished the pavers. I need to cut some to fit the dome shape. If the floor is wet, it does stay wet a long time, and should raise the humidity.
Yes, Ursula, the holding pond inside does raise the humidity a bit. It would be much lower if it didn't exist. You can see pics of the holding ponds on the Growing spaces website. I have a shelf across mine for plants that like more humidty. I could hang a few orchids above it.

Here are a few pics so you can have a better idea. In one you can see the under deck area that might be used for orchids. These were taken when it was first constructed, so it's still ugly on the outside. I haven't had a chance to do any landscaping.

I have deer roam through the yard but have never seen damage done to my orchids or for that matter, any of my tropical plants. They don't seem to like the plants I grow. What deer love are potato vines, both Irish and sweet potato leaves. I have to fence in my raised garden to keep them away from vegetables. One vegetable they won't touch is garlic.

Our area is remote and the area is in a drought, so the deer, rabbits and javelinas are hungry. They have even been eating my opuntias! Just for fun I planted a Nerium Oleander there, and it lasted only 2 days. Some animal ate it down to the ground. I thought all animals knew it was highly poisonous. I haven't found any dead animals, but I bet one of them doesn't feel too well. I did have Irish potatoes and the vines were eaten. When we get a chance we'll do a fenced veggie garden area. I've found they don't like garlic, onions or most of the herbal things like wormwoods or rosemary.