Seed Depth: ¼ inch

Seed Spacing: 8–12 inches

Sunlight: Full sun to partial shade

Days to Sprout: 7–14 days

Days to Bloom: 90–120 days

Plant Height: 18–30 inches

Plant Type: Annual

Sunlight: Prefers full sun but tolerates partial shade, especially in hot summer climates.

Soil Type: Well-drained, fertile soil with neutral to slightly acidic pH is best. Enrich with compost if needed.

When to Plant: Start indoors 6–8 weeks before your last frost or direct sow outdoors after frost danger has passed.

Direct Sowing: Sow seeds ¼ inch deep in loose soil. Thin seedlings to 8–12 inches apart after germination.

Indoor Sowing: Start in seed trays with a quality seed-starting mix. Keep moist and warm (65–70°F). Transplant when 3–4 inches tall and well hardened off.

Watering: Keep soil evenly moist but not soggy. Water at the base to avoid wetting foliage, which can lead to mildew.

Fertilizing: Feed every 4–6 weeks with a balanced, all-purpose fertilizer or compost tea to encourage healthy blooms.

Mulching: Apply a thin layer of organic mulch around the base to retain moisture and suppress weeds.

Staking: Taller plants may need light staking to stay upright, especially in windy areas or when heavily blooming.

Deadheading: Remove spent blooms regularly to encourage continued flowering and maintain tidy growth.

When to Harvest: Allow flowers to fully mature and dry on the plant. Seed heads are ready when the center turns brown and papery.

How to Collect: Snip off the dried flower heads. Gently break them apart over a tray to release the small, oval tan seeds.

Drying and Cleaning: Spread collected seeds out on a paper towel or screen in a cool, dry place for several days. Remove any remaining chaff or plant material.

Storage Tips: Once completely dry, store seeds in a labeled envelope or airtight container. Keep in a cool, dark, and dry location. China Aster seeds can remain viable for up to 3 years when properly stored.