This herbaceous perennial is a phenotype that is native to Saskatchewan in Canada. E. angustifolia is the most northerly ranging of all nine indigenous North American species. The plant prefers full sun and mesic, alkaline soils. Amend garden soil with limestone for best results. Sow in fall or early spring, directly into a prepared garden bed or in flats or pots and let the rain, snow, and cold temperatures awaken the seeds. Or, give the seeds 30-90 days cold, moist refrigeration and sow into warm soil. Thin or transplant to six inches to a foot apart.