Aquilegia atrata | Dark Columbine

Aquilegia atrata, also known as the Dark Columbine, is a striking perennial known for its deep purple-black flowers and delicate, fern-like foliage. It adds a touch of elegance to woodland gardens, borders, and cottage-style landscapes. 

Seed Treatment & Stratification

  1. Cold Stratify (Essential)

    • Mix seeds with a small amount of moist sand or peat moss.
    • Place in a sealed plastic bag and refrigerate at 35–40°F (2–4°C) for 4-6 weeks or longer.
    • Important: If seedlings emerge in the bag, remove them immediately and plant them carefully into soil.

  2. Alternative Method: Sow outdoors in late fall so natural winter cold will stratify the seeds.

Germination Conditions

  • Sowing Depth: Surface sow – press gently into moist soil but do not cover; seeds need light to germinate.
  • Germination Temperature: 65–70°F (18–21°C) after stratification.
  • Germination Time: Typically 21–56 days (AFTER stratification), but can take longer in some conditions. Be patient!

Sowing Indoors

  • Best started indoors 6–8 weeks before last frost.
  • Use seed trays with well-draining seed starting mix.
  • Mist soil gently to keep evenly moist—not soggy.
  • Provide bright indirect light or use a grow light.
  • Transplant seedlings outdoors after the danger of frost has passed.

Outdoor Planting

  • Choose a site with partial shade to full sun (shade preferred in hot climates).
  • Prefers moist, well-draining soil rich in organic matter.
  • Space plants 12–15 inches (30–38 cm) apart for airflow and growth.

Post-Germination & Care

  • Water regularly but avoid waterlogging.
  • Deadhead to encourage more blooms and reduce self-seeding.
  • Let some flowers go to seed if naturalizing is desired.
  • Mulch around plants to retain moisture and suppress weeds.