How to Propagate iris 'Before the Storm'?
Propagate by division of rhizomes from midsummer to early autumn; see dividing irises

iris 'Before the Storm' · Iris 'Before the Storm'
Grow in well-drained, fertile, neutral to slightly acid loam in full sun; sun on the rhizome encourages flowering. See also bearded iris cultivation
Propagate by division of rhizomes from midsummer to early autumn; see dividing irises