Propagating Japanese Maple (Acer palmatum) from Seed in the UK

Stratification and Sowing for Acer Seeds

1. Collect ripe seeds (samaras) in autumn; remove wings.
2. Store dry in sealed container in refrigerator.
3. Stratify: mix with moist sand/peat, bag, refrigerate 90–120 days at 34–40°F.
4. Sow in spring in 10-inch pots with good potting mix. Cover seeds to 3× their thickness.
5. Cover pot with plastic bag; keep moist. Germination in 30–60 days.
6. Remove bag; place in bright, indirect light or under fluorescents.
7. Keep soil consistently moist first 6 months.
8. When established, harden off: 1 week sheltered shade, then full sun.
9. Transplant to final location.

Caveat

Seedlings from named cultivars (hybrids) will not be true to type. For exact replicas, graft or layer. Species maples (e.g., A. palmatum wild type) come reasonably true.