How to Prune Dalmatian iris?
Remove any dying foliage in autumn, old flower stems can be cut down after flowering

Dalmatian iris · Iris pallida
Also known as: orrice root; orris root; pale blue iris; pale iris; sweet iris
Grow in well-drained, fertile, neutral to slightly acid soil in full sun
Remove any dying foliage in autumn, old flower stems can be cut down after flowering