Direct sow seeds very shallowly in spring, 4 weeks before last frost. Seeds require stratification, then light to germinate. Thin or transplant to 12” in all directions. Grows well in almost any conditions. Perennial. Will self-seed and spread.
Collect seeds from seed heads that are fully dry. Shell by hand, winnow or screen to clean. Some cross-pollination may occur, isolate from varieties of the same species by 1/4 mile.