It's difficult to say what's easy. I have a sophronitis cernua that is struggling to survive and other plants that do well. That doesn't mean those plants are easier to grow, they just fit better in my situation.

That being said my list would be

Aerangis citrata & mystacidii

Dendrobium loddigesii

Schoenorchis, gemmata & tixieri

Encyclia tampenesis

Sophronitella violacea

Leptotes pohlitinocoi

I'm sure there are many more, I grow the above mounted or in baskets. All are small and easy, at my house.

On a side note, why are Sophronitis so exspensive. I have wanted to try coccinea but the prices always seems high, $40 and up.

What might be easy in say San Francisco, might be just about impossible in say Florida without a cool house. Dendobium loddigessii is one of those which needs the drier winter. The sixty four dollar question is how much more dry is drier???

I grow Encyclia tampensis with no trouble at all underpotted. Do not know how it would go on a mount.

As for the lovely Sophronitis coccinea, it is rarely seen around these parts. Cultivation difficulty might be the reason for the expense.

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My choice is gastrochilus. I had gastrochilus bellinus on grape vine, orchid was growing just fine even here, in Alaska. Another candidate is dendrobium loddigessii. Plant grows on cedar wood slab really well. I provide additional light in the winter, of course.

Northern Orchids, how well does d.loddegessiae do for you? There are some amazing specimens of it pictured online. What's your typical humidity level during the heating season? Would an untreated white cedar shingle work as a mounting slab?

Miniplants, those vases and globes on the site look pretty good. If either of you would like to swap for seedlings of s.cernua once the weather warms up again, jlmk.

Here's a picture of my s.cernua, which I've had for 10+ years.

--Rick in CT

My vote is for orchids with terete pencil like leaves: leptotes and brassavola for example. these have preference the best for me mounted in a windowsill.

Out of curiosity, why the focus in slab culture?

Oh, sorry for late replay. My dendrobium loddigesii growth on red cedar wood slab, but I attached this slab to cork slab. Humidity is low during heating season, like 27-30%. I installed good lights but it is not enough. So plant is growing but not blooming.

it's not really a 'focus', except of this particular thread, but those orchid species that lend themselves to slab culture are of interest bc the watering is (for me at least), easy to control, and the miniature orchids display nicely on the slabs when they're in flower.