The Giving Garden – Rethinking the food-medicine continuum in the urban sprawl

FEB 24, 2025

Crop of the month: Amatungulu/Natal Plum/Large Num-num 

Across South Africa, amatungulu (Carissa macrocarpa; Apocynaceae) are a common sight in urban landscapes. This large, spiny shrub has dark green foliage and responds well to trimming, forming dense hedges which give the plant its popularity. In the wild, the species is found growing along South Africa’s Eastern coastline in the coastal bush, dune thickets, and forest margins of the Thicket and Indian Ocean Coastal Belt biomes.

Flowers are formed on new growth, and so are not as commonly seen in hedged plants. However, when left to grow the plant will flower prolifically producing masses of white, scented flowers which attract a wide range of insects and, by extension, insect-eating birds. Flowers have five petals united into a tube which is characteristic of the family Apocynaceae to which the species belongs. Flowering mainly occurs from late spring to early summer, but under ideal growing conditions the plant will produce small numbers of flowers almost continually throughout the year.

Amatungulu flower. Photo by Codyorb (https://en.wikipedia.org/wiki/File:Close-up_photo_of_Carissa_Macrocarpa_flower.jpg) 

The fruits are fleshy with a deep red colour when ripe. The flavour is a tangy mix of sweet and sour, and the fruits can be eaten fresh or used to make jams and jellies. These fruits are nutrient-dense and a good source of vitamin C, calcium, magnesium, and phosphorous making them a great addition to any edible landscape. The deep red colour of the fruits is also used to make an attractive dye.

Carissa macrocarpa is relatively easily grown from both seed and cuttings. Once established the plants are incredibly hardy due to their adaptions to the coastal belt, and will tolerate drought, light frost, salt spray, and full sun to semi-shade. As well as being used as a hedge, the species is also commonly used in rockeries and retainer walls, as a pot plant, and as a wind barrier. There are also several selected growth forms in the horticultural trade, including prostate-growing selections which make an attractive ground cover.

This species is among the easiest indigenous fruiting species to grow in South Africa and is already a popular choice in the landscaping industry, making it widely available from retail nurseries. As such, Carissa macrocarpa is a great starting point for anyone looking to add more indigenous edible plants to their garden.

 Richard Hay

Curator: Future Africa Indigenous and Orphan Crops Collection, Manie van der Schijff Botanical Garden, University of Pretoria

BotSoc Conservation Project Coordinator, Northern Region

richard.hay@up.ac.za or north@botanicalsociety.org.za

Jason Sampson

Head Curator: Manie van der Schijff Botanical Garden, University of Pretoria

jason.sampson@up.ac.za