Surface sow or barely cover; requires light for germination.
2 months after chill
Stratify for 3-6 weeks in late winter. Sow in a container, cover with a plastic bag and refrigerate, or mix seed with damp clean sand or vermiculite, bag, and refrigerate at 35-40F. Check often for germination and maintain a lightly moist medium. Transplant any seedlings as they germinate. Six to 8 weeks before last frost, remove pre-chilled seeds from refrigerator and sow in pots. Cover with humidity dome to retain moisture while seeds germinate. Keep at 60-70°F. Water from bottom once germination has occurred, and allow to drain thoroughly.
Direct sow in fall or earliest spring, or wintersow into pots in the shade, covered with a thin layer of clean sand and a wire screen to keep out mice and voles. Check for moisture at regular intervals. Germination rates outdoors may vary depending on weather conditions—be patient.
WHEN TO SET OUTSIDE
This summer bloomer can be set in the ground in spring after the last frost while the soil is cool. It can also be planted in early autumn.
PLACEMENT & CULTIVATION
Showy milkweed will attract butterflies, especially monarchs, and is resistant to deer browsing. In the wild, it grows in fields in well-drained dry soils. It is well-behaved in beds and gravel gardens as it is more clump-forming than spreading. Deadhead, if desired to curtail any self-sowing, and wear gloves, as the milky white latex can irritate some. Caution: handle carefully, as all parts are poisonous, but toxicity is concentrated in the sap.
Adaptable as to soil moisture, growing in wet and dry areas. Once established water during dry spells.
Most pH levels are tolerated.
Milkweed is not a heavy feeder, a yearly application of a half inch of compost is adequate.
Diseases & Pests:
No major pests or diseases.
When to Cut for Bouquets:
Cut when florets are mostly open for fresh arrangements. Plants have a milky sap. For dry use cut when seed pods have started to dry.