Flowering plants for a wabi-kusa?

[Kehy]

I made my mom a nice wabi-kusa awhile ago, and apparently it's been noticed by a coworker that's really fascinated with it. She's asked if I could make her one, with flowering plant/s.
I know that ludwigia blooms really easy, but it's blooms are really nothing special. Are there other easy blooming plants that would work in a wabi? I was thinking a peace lilly, but I've never grown them, especially wet.