J, take a look at the project thread as Haraella retrocalla was a project plant on OB in spring '09, so lots lof people here were growing them and comparing notes.
I'm not certain, but you may pick up some tips about how people in the project were growing them.
What a beauty this little plant is! After reading the entire "Sprint 09 Project" thread, I had to order one, too, of course It's still in bloom, but it came in spike, so I can't take credit for it. We'll see how I do with this cutie next year.