Pinus thunbergii (Japanese Black Pine) Seeds
Zones: 5 to 8.
Native to Japan.
The Japanese Black pine is a beautiful evergreen conifer that graces Japanese gardens where it is often trained in the Niwaki style. It grows naturally in the Japanese landscape and is especially prominent along coastlines. It has a dense, bushy habit especially when young, becoming more open in older trees. It has dark green needles up to 5 inches (12 cm) long in bundles of two. Cones are brown coloured and 1.5 to 3 inches (4 to 7 cm) long. The bark is grey in younger trees, changing to almost black and plated on mature trees.
With its elegant form the Japanese Black pine is trained as a classic bonsai specimen.
The Japanese Black pine does best in moist well-drained soils and prefers a site with full sun. It is salt tolerant and grows well in coastal areas. Established trees also show some drought tolerance.
Size: Height 20 to 60 ft; Width 12 to 20 ft.
Scarification: Scarify the seeds by lightly sanding or filing them and placing them in water to soak for 24-48 hours before beginning stratification.
Stratification: Provide 60 days cold moist stratification at 3° C (37° F) to 5° C (41° F).
- Soak seeds in water for 24-48 hours.
- Place seeds in sandwich bag(s) with a bit of damp sand or vermiculite to keep moist.
- Place the bag(s) with seeds in refrigerator for about 60 days.
- After the required time take the seeds out of the refrigerator and sow the seeds in pots 1/4 inch deep and cover lightly. Water gently so as not to wash away the seeds. Keep soil moist but not wet.