I am very interested in corn lilies growing in the Seattle area, and I would like to know how to grow them and where to find some.
In the fall, corn lilies (Ixia) have already done their flowering, and I do not know of any place to send you to see them. They aren’t common, but some avid local gardeners do grow them.
Regarding how to grow these bulbs, the following is quoted from Sunset Garden Book (2001), pp. 406-407:
African Corn Lily:
Clump of narrow, almost grasslike leaves sends up wiry, 18-20 inch stems topped by short spikes of 2 inch flowers in late spring. Each six-petaled blossom opens out nearly flat in full sun but remains cup-shaped or closed on overcast days. Colors include cream, yellow, red, orange, and pink, typically with dark centers. Most Ixias sold are hybrids of the South African species Ixia maculata.
Grow in well-drained soil. Where winter lows usually stay above 20 degrees F, plant corms in early fall, setting them 2 inches deep and about 3 inches apart. … Let soil go dry when foliage yellows after bloom. Where corms will not be subject to rainfall or irrigation during dormant period, they can be left undisturbed until the planting becomes crowded or flowering declines. When this occurs, dig corms in summer and store as for gladiolus until recommended planting time in your area (the nursery can tell you this). Where corms will receive summer moisture, dig and store them after foliage dies back; or treat as annuals. Potted corms (planted close together and about 1 inch deep) can be stored in pots of dry soil.
Be careful not to pull them up accidentally, as the new growth in spring looks a lot like grass!