Agastache rugosa (Korean Mint)

Seed Preparation

  • Place seeds between damp paper towels in a sealed bag
  • Refrigerate for 5–7 days (not more than 10 days)
  • Monitor daily — if seedlings emerge, remove immediately & plant

When to Sow

Indoors:
Late winter to early spring (6–8 weeks before last frost)

Outdoors (direct sow):
After last frost, once soil warms (mid-spring to early summer)

Germination Details

  • Optimum temperature: 20–22 °C (68–72 °F)
  • Germination time: 7–40 days
  • Light required: Light is beneficial — surface sow, press gently into soil without covering fully

How to Sow

Sow seeds on the surface of moist seed-starting mix
Do not cover heavily — they need light
Mist lightly & cover with a humidity dome or plastic wrap
Place in warm location with indirect light
Keep soil moist but not soggy

Post-Germination Care

  • Once seedlings appear, remove cover & place under bright light
  • Maintain soil moisture but avoid waterlogging
  • When seedlings have 2–3 sets of true leaves, transplant carefully
  • Harden off gradually before moving outdoors

Growing Tips

Full sun to light partial shade
Water moderately — drought-tolerant when mature
Well-draining soil; avoid soggy spots
Good air circulation prevents mildew
Deadhead spent flowers to encourage more blooms
Attracts pollinators & makes lovely cut flowers

  • Perennial in USDA zones 4–9