Having many different names, some of them difficult to pronounce, may relegate a plant to obscurity, unless the plant’s qualities render it highly desirable. Such is the case with the mgambo tree known botanically as Majidea zanquebarica or Zanzibar soapberry and locally referred to as weleweka or Hawaiian pussy willow. This tree is also known as the black pearl tree, the velvet-seed tree and the Maui mink tree.
Having many different names, some of them difficult to pronounce, may relegate a plant to obscurity, unless the plant’s qualities render it highly desirable. Such is the case with the mgambo tree known botanically as Majidea zanquebarica or Zanzibar soapberry and locally referred to as weleweka or Hawaiian pussy willow. This tree is also known as the black pearl tree, the velvet-seed tree and the Maui mink tree.
Most of this tree’s names are descriptive of the remarkable seeds the tree produces but they don’t refer to its other outstanding qualities. In hot, dry, sunny areas, the tree usually remains small (under 15 feet) and its rounded canopy of shiny green compound leaves provides shade. The mgambo produces panicles with dense clusters of tiny light green, fragrant flowers that develop into three-lobed seed capsules. When the fruit splits open, the plant becomes a show piece. The pod reveals a bright red interior where round dark grey velvety seeds are nestled. These remarkable features remain on the tree for several months. The seeds are often used to make lovely jewelry and the red pods offer attractive additions to bouquets or potpourris.
Majidea zangueberica is native to tropical east Africa and is a member of the Sapindaceae or Soapberry family. Its close relatives include rambutan, longan, litchi and the indigenous Hawaiian aalii. The Swahili word mgambo means “announcement” or “proclamation” and it also refers to the showy fruit and seeds the tree produces. The first mgambo probably arrived here from Sri Lanka in the early 1960s and several large specimens can be found on Oahu with a few smaller ones reportedly here on the Big Island.
Though the tree is a bit hard to find, it is well worth the search. Call local nurseries to see if they have mgambo trees in stock. Sunrise Nursery can occasionally get them if you call to request one. Several sources of seed are listed online.
If you can’t find a tree in a nursery, find someone who has one. You can grow your own mgambo from seeds or cuttings. Seeds should be placed in hot water and soaked for 24 hours to prepare them for planting. Plant in a good seeding mix that contains some perlite and maintain a moist medium until the first true leaves appear. This can take six weeks or more. At this point you can up-pot and apply some slow release fertilizer.
When it is ready to outplant, select a spot in full sun that gets regular watering. Mgambo can tolerate some drought and will stay smaller where the water supply is limited. Healthy mgambo trees are not usually vulnerable to diseases or insect attacks. Occasional whiteflies or spider mites may appear and can be treated with a sprayed combination of neem oil and safer soap mixed in water.
Diana Duff is a local organic farmer as well as a plant advisor and consultant.