The dark-leaved plectranthus, at least, can get by with very little light. I bring some in before frost and set the container on a shelf in a low-light window on a humidity tray. I forget about it until it looks half-dead
and then water it well. So far, I haven't lost one yet, even though I'm a terrible houseplant gardener. These plants like indirect but bright light and a high nitrogen fertilizer while blooming, but don't need any extra fertilizer when they aren't. They'll even bloom a bit in low-light conditions, but the flowers will be very pale.
These plants root very easily, so if indoor space is limited, just pull a piece of stem from the root ball and tuck it into a small pot of moistened mix.
This picture isn't of the exact same cultivar, but this is what the bloom looks like indoors at the tail-end of our long, dark and gloomy winter.
Outdoors in bright, indirect light the bloom color is much darker.
Leaf tips and edges tend to burn in too much direct sun.
to ATP. I forgot to welcome you in my above post. 
