Answer: Every gardener will probably come up with a different list; gardening is a very personal thing!
Difficult: Bird of Paradise which takes years before it will flower indoors, outdoors would be delphinium
Touchy: orchids indoors, hybrid tea roses outdoors
Ever blooming, easy: African violets will bloom off and on all the time if they have enough light (contrary to common belief they are not that difficult and very few indoor plants are everblooming) indoors; outdoors would have to be marigolds.
Good luck with your screenplay!
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