Japanese Maple Seed Collection and Stratification Protocol

When to collect Acer palmatum seeds?

Collection

Late summer/early fall (Aug–Sep) when samara wings begin turning brown. Don't collect earlier—seeds may be immature.

Germination Process

1. Soak seeds 48 hrs in lukewarm water
2. Mix with damp sphagnum/peat in zipper bag; 4–6 weeks room temp
3. Stratify: Refrigerate 60–90 days (mimics winter)
4. Sow ¼" deep in seed compost at 65–70°F
5. Transplant to 2–3" pots when handleable

Note: Sporadic germination; requires refrigerator space!