Macleaya cordata

Germination

Sow indoors at any time. Sow into a cold frame in autumn. Indoors, surface sow onto moist, well-drained seed compost. Ideal temp. 18-22°C for 2-4 weeks. If germination does not occur cold stratify. Move to -4-+4°C for 4-6 weeks, a fridge is ideal, then return to warmth for germination. Germination can be erratic. Transplant seedlings when large enough to handle. Acclimatise and plant out after danger of frost has passed. Cold frame, allow autumn warmth followed by winter cold to offer ideal conditions for germination to occur in spring as the weather warms.

Growing

Prefers a deep moderately fertile, moist but well-drained soil in full or partial sun. Offer protection from cold winds. Slow growing in the first season but can then spread rapidly.

Cultivation

Cut the plant back to the base in late autumn. Propagate by division in late autumn or spring. Separate root rhizomes in winter when dormant.