Spekboom is nutritious, water-wise and edible – so why aren’t more South Africans eating it?

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Spekboom (Portulacaria afra) is an easy-to-grow succulent shrub, small tree, or hedge.

In the wild, it grows naturally to up to five metres tall on steep slopes and rocky hillsides in the Karoo and Eastern Cape regions of South Africa, where it helps to stabilise soil and prevent erosion. It's also a champion of carbon sequestration – removing carbon dioxide from the atmosphere.

Because its fleshy green leaves store an exceptionally high average moisture content of over 93%, spekboom is also a natural water source for both people and wildlife in arid regions.

But what about eating spekboom for dinner?

We are scientists who explore how underused indigenous plants, crops and insects can become safe, nutritious and appealing foods. We already know that spekboom is a good source of vitamin C. So we set out to do two things. First, we tested the colour, appearance, texture, moisture, acidity and vitamin C content of raw spekboom leaves and leaves that had been baked, stir-fried, steamed or blanched. We wanted to see how cooking changed the leaves and whether they could be prepared and eaten like other leafy vegetables.

Second, we explored what consumers knew about spekboom as a food and whether they would be willing to eat it.

Our research found that cooking made spekboom leaves lighter and softer while maintaining qualities similar to other leafy green vegetables. Although the people we surveyed knew little about spekboom as food, most were willing to eat and buy it, even though they hadn't tried it.

The benefits of raw and cooked spekboom

Raw spekboom leaves are juicy and crunchy, with a sharp taste similar to lemon juice. Their natural acidity makes them useful in both raw and cooked dishes because it balances sweetness and spices. The leaves can be eaten fresh or used to make tangy relishes, crunchy pickles and sweet preserves.

But to broaden the consumption of spekboom, we needed to find the best way of cooking it in everyday meals. Science honours student Rozanne MacDonald developed several recipes for cooking spekboom that we tested in our Sensory Laboratory in the Department of Sustainable Food Systems and Development at the University of the Free State.

For a spekboom-and-lemon curd, we blended fresh leaves with lemon juice and cooked the mixture with eggs, sugar, lemon zest and a little cornflour until it thickened, before whisking in butter. The result was a smooth, sweet-and-sour spread that can be refrigerated in a sterilised jar for up to 10 days.

Spekboom can also be used in savoury preserves. We added fresh leaves to a tomato chutney made with onions, garlic, vinegar, sugar, garam masala, mustard and herbs. The tomatoes were cooked slowly until reduced before the spekboom was added for the final 30 minutes.

We also pickled fresh leaves with thinly sliced red onion in a warm mixture of red-wine vinegar, honey, olive oil, fennel, mustard, cinnamon and cardamom, then left them for seven days before serving.

Dried spekboom leaves can also be turned into dukkah, a crunchy Egyptian-style seasoning. We mixed crushed dehydrated leaves and spekboom powder with toasted coriander, cumin, sesame and sunflower seeds, hazelnuts, peanuts, salt and black pepper. The spekboom added acidity to the rich mixture of nuts and spices.

These dishes show that balancing its lemony flavour with sweet, savoury or spicy ingredients can produce foods that people genuinely enjoy.

Overall, we found that the cooked leaves remained acidic and moisture-rich, much like other fresh leafy vegetables. Vitamin C levels were higher than raw leaves after steaming the spekboom leaves.

But will people eat it?

A plant can be sustainable, but if people don't like the taste and won't eat it, then it's no good for solving food security issues.

We asked 120 people this question. About 84% of the group had seen spekboom before, but only 22% had eaten it more than once in the previous year. Only 3% of the group knew that spekboom was nutritious, but 82.5% said they'd be more likely to eat it if they knew more about its health benefits.

Overall, most of the group were interested in eating spekboom: 79.2% said they were willing to use it in their diets, and 75% said they would buy it if it was available in supermarkets. More than 77.5% would consider buying it if it cost less than other vegetables.

This suggests that spekboom is a widely recognised but rarely considered food, and that people are open to eating it. Better information about its health benefits, ways of preparing it, supermarket availability and an affordable price could encourage its use as another leafy vegetable.

What needs to happen next

South Africa's food system is failing many people: poverty, inequality and unemployment leave households unable to afford enough nutritious food. About 63.5% of households in the country do not have enough food, with 17.5% described as critically undernourished in 2024. Eating indigenous plants like spekboom could improve the current food system in South Africa.

Spekboom requires very little water, thrives in poor soils, and is very resilient. Processing it into shelf-stable products like relishes and preserves could reduce post harvest waste and create sustainable value chains. It opens doors for local community agro-processing initiatives, turning backyard plants into marketable, value-added food products.

Spekboom should not be just an emergency food to forage or a novelty salad garnish. With the right culinary approach and food-science backing, our research shows that spekboom has the potential to go from being from an outdoor hedge to a staple in modern African kitchens.

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

By Alba du Toit, Professor and PARC/DoA/UFS Chair: Innovative Agro-processing for Climate Smart Food Systems, University of the Free State And

Faith Matiza Ruzengwe, Postdoctoral Research Fellow, University of the Free State