I have some extra plants under some of my bananas; got cannas out back under the Blue Javas & in a couple pots of various pups that have been whacked out of the mother mat, Nicotiana rustica is occupying the open spots, what little of it there is.
The N. rustica will start to wilt a little when it's time to slop some water in the pots, so it's sort of an "indicator" that keeps it's big brothers from getting over-watered.
I'd say slap in whatever ya want & see how it goes, doubling up on real estate is a good way to get the most out of a limited amount of planting space.
