Syringa josikaea (Hungarian Lilac)

Seed Treatment (Cold Stratification Required)

Cold Stratification Method:

  1. Soak seeds in warm water for 12–24 hours to soften the seed coat.
  2. Mix with moist sand, peat, or vermiculite.
  3. Place in a sealed plastic bag and refrigerate at 35–40°F (1–4°C) for 90 days.
  4. Check periodically to ensure the medium remains moist but not soggy.

Sowing Instructions

  1. When to Sow:
    • Indoors: Start seeds immediately after stratification in late winter to early spring.
    • Outdoors: Sow in late fall for natural stratification over winter.

  2. Soil Requirements:
    • Prefers well-draining, fertile soil with a neutral to slightly alkaline pH (6.5–7.5).
    • Avoid heavy clay soils unless amended for better drainage.

  3. Light Requirements:
    • Requires full sun (at least 6 hours of direct sunlight daily) for best growth and blooming.

  4. Sowing Depth:
    • Sow seeds ¼ inch (6 mm) deep in seed trays or pots.
    • Cover lightly with fine soil and gently firm.

  5. Watering:
    • Keep soil evenly moist but not waterlogged.
    • Use a mist spray to water gently during germination.

  6. Germination Time:
    • Germination can take 30–90 days, even after stratification.
    • Be patient — lilacs are slow to start from seed.

  7. Spacing & Transplanting:

    • When seedlings have developed a few sets of true leaves, transplant into individual pots.
    • Once established, space plants 3–6 feet (1–2 meters) apart in the garden.

Growing Tips

  • Syringa josikaea is a cold-hardy, fragrant lilac species known for its late-blooming, tubular pink-lavender flowers and excellent mildew resistance.
  • Attracts bees, butterflies, and hummingbirds, making it great for pollinator gardens.
  • Prune immediately after flowering to maintain shape and encourage next year’s blooms.
  • Water regularly during dry periods, especially in the first year after planting.
  • Deer- and rabbit-resistant once established.

Enjoy the long-lasting beauty and sweet scent of this underappreciated lilac, perfect for hedges, wildlife gardens, and perennial borders.