Question
I planted 4 stella d'oro daylilies last year & I need to stop the endless runners invading the bed & even under the edgers & into the grass. Its only near 1 of the origional plants but I realize the runners could be from the others too. The bed is the same for all 4 so I can't understand why 1 would invade & not the others or do they all invade? Should I get rid of just the one or all of them or is there a way to contain them like by planting them in terracotta pots in the soil? Tks!

Answer
Hi J

Your stella d'oro daylilies are not in fact lilies at all! They are Hemerocallis!  Their common name is Day Lily.  This is because the flowers resemble lily flowers and each flower only last for 1 day (usually).

Most Hemerocallis form large clumps over time.  Your stella d'oro is one of the few that form runners (rhizomes)!  The only way to control them in the ground really is to dig around each plant and remove the invading rhizomes!  You could try putting one of the plants in a  terracotta pot away from the others and 'wait and see', it certainly works with some other plants which spread by the same method.

You must have given them some really good soil!