Seeds from Nemastylis geminiflora Celestial Ghost Iris. The sky-blue flowers open in late morning and curl up before 3 in the afternoon, even on overcast days. Each flower only lasts one day. Once the seed has ripened, the bulb is renewed and the plant disappears until following spring. The bulbs colonize over time. Perennial Herb. Normally 6 to 12 inches, but can reach 18 inches. Flowers 1 to 2 inches wide. Zones 6-9.