How to Prune daylily 'Cosmic Blast'?
Deadheading will improve appearance, and can help reduce hemerocallis gall midge. Cut back flower stems after flowering has finished. Remove dead foliage as required

daylily 'Cosmic Blast' · Hemerocallis 'Cosmic Blast'
Grow in fertile, moist but well-drained soil preferably in full sun. Flowering is likely to be poor in shadier situations. Tolerant of heavy clay and poorer soils. May need watering in spring to early summer in dry conditions to ensure flowering. See Hemerocallis cultivation for details
Deadheading will improve appearance, and can help reduce hemerocallis gall midge. Cut back flower stems after flowering has finished. Remove dead foliage as required