Probably referring to Setaria.
http://flowerknight.wikia.com/wiki/Green_Foxtail
I think German Iris looks cuter...
http://flowerknight.wikia.com/wiki/German_Iris
I'll pass on the rainbow though, I'm already happy with my Daisy.
http://flowerknight.wikia.com/wiki/Kerria
And the event unit herself is cute, if you somehow missed her.
http://flowerknight.wikia.com/wiki/Hypericum