Black mangrove (Avicennia germinans)

Product description

The black mangrove grows along the coasts of tropical America and West Africa, where its unusual roots are striking. The aerial roots protrude straight up from the soil and are branches of long, underground cable roots. These aerial roots allow the tree to absorb oxygen, which would otherwise be scarce due to the mud and seawater. Like other mangroves, this root system provides coastal protection, but the upright roots of this species also help to retain sand. This allows the coast to expand naturally. 

While the red mangrove (Rhizophora mangle) often grows in the water, the black mangrove grows slightly further inland. It grows in areas that are flooded at high tide but dry out at low tide. Unlike the red mangrove, the black mangrove also has salt glands on its leaves, which allow excess salt to be removed. Small droplets of salt water form under the leaves, where they dry and form salt crystals. This gives the leaves a white underside.
 
The seeds of the black mangrove are viviparous, which means that they begin to germinate while still attached to the tree. For best results, plant the seeds in well-drained, airy soil. A mixture of potting soil, sand and perlite generally works well. Keep the soil constantly moist, but not waterlogged, so that the roots get enough oxygen. The plant grows best in full sun. When aerial roots form, it is important to provide a large pot.

Sowing description: Sow the seed with the already visible root pointing downwards in well-drained, airy soil. Just deep enough so that the seed is no longer visible. Place the tray in a sunny spot at a temperature of around 25-30 degC.