Are you referring to any particular plant genera?

Tropical dendrobium orchids have been crossed to temperate Australian species to produce "tropicool" hybrids for Australian conditions. These would do well in California.

People are also crossing tropical vandas to temperate neofinetias as well as temperate Sarcochilus to Phalaenopsis.

Here is a link that might be useful: Elanbee Orchids

adamharbeck, I'm interested in learning about cool x warm hybrids from any genre. I'd like to figure out whether such hybrids tend to have a wider temperature grow range (TGR).

Thanks for sharing the info about the "tropicool" hybrids. I think that with most of those hybrids...the TGR of the warm/tropical parent fits inside the TGR of the cool parent. For example, I have both Dendrobium bigibbum and Dendrobium kingianum. Here's kinda when they grow...

Spring (intermediate) - D. kingianum
Summer (warm) - D. kingianum, D. bigibbum
Fall (intermediate) - D. kingianum
Winter (cool)

So crossing them probably wouldn't produce a hybrid with a wider TGR. The D. bigibbum could help contribute drought/sun tolerance and flower color/shape/size... but it wouldn't help lengthen the grow season. In order to lengthen the grow season we'd need a cool growing Dendrobium. Both D. kingianum and D. bigibbum are tolerant of cool temperatures...but I'm not sure if D. kingianum is a cool grower. It actually might be but perhaps mine do not receive enough winter water to grow.

I think it's the same thing with Neos and Sarcs. They are certainly cold tolerant...but I'm not sure if they are cool growers.

In my blog entry...the cool growing examples I used were Dendrobium falcorostrum, Drymoanthus adversus and Encyclia vitellina.

Perhaps it helps to think of a tall mountain like Mt. Kinabalu. If you cross a Coelogyne that grows at the base of the mountain with a Coelogyne that grows at the top of the mountain...where on the mountain would the hybrid be able to grow?

This last winter I tried to continue regularly watering a few of my orchids... Hercuthermal Experiment. If anybody is interested in some discussion on the topic... Prosthechea vitellina.

Interesting. I wonder if the warmer winters in recent years played a part in the results. Nowadays, I tend to keep what turns out to be no-fuss, water-with-everything-else year-round orchids. I water as needed overall, which is less frequent during the cooler months.

I did get a Cymbidium aloifolium recently that I [try to remember to] bring under cover in the evenings, until the night temps warm up. It will likely end up being a sink or swimmer outdoors, too, though.

gyr_falcon, yeah, I'm not sure if the Bpl Golden Peacock (GP) would have continued to grow if the winter had been any cooler. But... in any case, the GP continued to grow while the nodosa did not. So the nodosa only grew for half the year... while the GP will grow the entire year. This disparity in growth is quite interesting because it's so large. It will take the GP a lot less time to become a specimen plant. Well... assuming that I continue regularly watering it year around!

I've had Cymbidium aloifolium and Cymbidium madidum growing at the top of my tree for years now. They are both pretty happy but spotting their flowers from the ground is... challenging. If I had to do it all over again I probably would have put some hummingbird pollinated orchid (GP, Guarianthe aurantiaca, etc) in that spot instead of the Cymbidiums. The Cymbidiums are nice.... but they aren't as nice as orchids that are pollinated by hummingbirds!

A recent photo of both Cymbidiums blooming on my tree...

<a href="https://www.flickr.com/photos/epiphyte78/26225345290/"><img src="https://c2.staticflickr.com/2/1559/26225345290_7904249891_z.jpg"></a>;

That should work. But... it doesn't.

I guess I'll click the photo icon and upload it...

That is really nice! I have a thing for cascading flowers. (And weeping trees, now that I think about it.) Wish I could more easily grow some of mine on trees. Unfortunately, the trees in my setting are either too young, or not shaped in a way to easily use them to grow orchids. Watering is always a problem, too. Although I do have a single mist head for the bromeliads, it is on the line with the regular plant system, so cannot be set to spray as often as would be needed for epiphyte growers in this dry climate. If I can ever snag a hunk of a fallen tree with some character, I will use that. Wish driftwood chunks didn't run several hundred dollars, and up, locally. Thanks for sharing your photos.

that just means you need another irrigation circuit. lol

:D yeah. The clock is maxed out. But that isn't even the biggest problem. It is the trenching to get to the tree, through compacted soil containing drainpipes that are extremely brittle We learned to minimize our encounters with it early on; simply cutting the pipe to repair one crack results in more cracks down the line. The line goes from a few inches under the surface to the final exit, which is 4' deep under established plantings. I'm not opening that can o' worms!

I love hanging/cascading/pendent plants as well. Here's one of my favorites...

During summer I only water it twice a week at night. First I quickly hit the tree with the hose and then I water the rest of that section of the garden. When I'm finished I connect the hose to the polytubing at the base of the tree. I turn the hose on and leave it running for around 20 or so minutes.

But for the rest of my trees I don't bother with a drip system. I can easily water all the orchids on them with the hose. None of my other trees are three stories tall.

Regarding your scarcity of suitable hosts... I think that quite a few trees can easily be grown from fairly substantial cuttings. The next time you lop a large branch off a tree... stick it in a pot and see what happens. Yesterday I took a pretty large branch from each of these three trees...

- Plumeria
- Privet
- Mulberry

... and stuck them all in the same 5 gallon pot with some reasonably well drained mix. Plumerias can definitely grow from fairly large cuttings. Pretty sure the same is true of the Privet. Not sure about the Mulberry though.

Plenty of Ficus are more than happy to grow from large cuttings. My uncle recently told me that Moringa can grow from large cuttings and it's a really fast grower. Lots, if not all, tree Aloes can be grown from large cuttings. Same with Aralias, Pachiras, Cordylines, Dracaenas and Yuccas.

Last year I lopped some branches off my Mexican Palo Verde. I stuck the two largest ones in pots. Right now the branches are as green as when I potted them... but they haven't sprouted yet.

I'm pretty sure that pomegranates can be grown from large cuttings. I've definitely grown grapes from large cuttings.

I've also grown Bougainvilleas from large cuttings. Same with the Cup of Gold vine.

If you search eBay for pre bonsai, lots of them have probably been grown from cuttings.

lol When I was a young child I remember my mother taking 6' elm branches and just sticking them in the ground. I thought she was nuts (well, she was, but this didn't turn out to be a good example of that). Several of those things grew and became trees.

I probably didn't answer clearly, though. Our plot is only about .17 acres, and already contains 10 trees that are 9' and taller. Many are deciduous for part of the year, so epiphytes growing on them would fry. I'm hesitant to take on more hand watering as I'm already beyond the comfortable time necessary to water the pots I have now. I could maybe do twice/week, but I cannot get by on that for my potted plants now, so I am worried that our location would require more frequent irrigation. I'm brainstorming and may have something creative in mind that I have to check out when it gets light to see if it is feasible. It won't ever be as grand as your tree by a long shot, but maybe it could be nice.

well a maxed out timer is definitely a problem. One that is easily solved with a cheap timer from ebay. lol

Trenching? meh, just run black poly through the back of the bed and mulch it.