Daylilies flower for one or more months during the summer. Though the flowers appear as if they are constantly in bloom, they are actually different flowers every day. Each daylily bud blossoms once for a single day. It fades at the end of the day, but the bloom is quickly replaced with another bud that opens and flowers. Removing the old blooms regularly prevents seed production. Old flower removal prolongs the flowering period and improves the appearance of the daylily plants.
Daylilies yellow and die back to the roots in fall. Cut back the old foliage to ground level only after it dies naturally.
Allow some seed pods to develop and dry fully on the plant if you wish to harvest seeds for planting.