I am certain they need to be divided and fed. One of my major novice mistakes was to move what I thought were dwarf bearded irises down from the top of the slope and planted them in a couple of the rose beds. Those ten inch irises grew to four feet ! The took out all of the beautiful foliage at the base of the roses, too.
Maybe I'll get up there some day, but I want to finish the beds I've started so that it doesn't look like I am growing just roses and weeds.
Smiles,
Lyn
