Robinia pseudoacacia (Black Locust) Seeds
Zone: 3 to 9.
Native to southeastern United States.
The black locust is a medium sized deciduous tree native to the United States and naturalized in many parts of the world. As a member of the pea family it has nitrogen fixing properties in the soil, which allows it to thrive even in poorer soils. Leaves are pinnately compound, with a single leaflet at the tip and 3 – 9 pairs of leaflets along a central stalk. In early summer it has clusters of white pea-like flowers after the leaves have developed. The fragrant flowers attract bees, which produce honey from their nectar. It develops flat, reddish-brown, seed bearing pods that mature in autumn and may remain on the tree through winter. On mature tree the bark is greyish-brown and furrowed. The tree usually has a forked trunk, an oval canopy and open branching. The black locust is fast growing and thrives in average, moist, but well drained soil, however once established it is drought tolerant. If chopped down the black locust will likely grow new shoots from the trunk and form a new tree.
Size: Height 50 to 80 ft; Width 30 to 50 ft.
Scarification: Black locust seeds have a very hard seed coat on them which needs to be broken down before the seeds can germinate. Sand or file the seeds and/or carefully nick the outer coating with a pocket knife. Be careful not to go too deep into the seed itself. Then place seeds in a container with hot water and let the water cool to room temperature. Leave the seeds in the water for 12 to 24 hours until they show signs of swelling. If not, repeat the previous steps. When seeds show signs of swelling, sow them in pots. Keep the soil moist but not saturated. Seeds should germinate within a few weeks.