A tough Nut to Crack

It is widely recognised that South Africa, especially the fynbos region, is being overrun by invasive alien vegetation from Australia. Think of all the Port Jackson willow, Australian myrtle, black wattle and Rooikrans (Acacia cyclops), to name but a few.

But are there any Australian trees that are not invasive and make a positive contribution to our economy? Yes, indeed. One such tree is the Macadamia, which is a genus of the Proteaceae family. (In a previous article I explained how this ancient plant family travelled around the world when Gondwana broke up.) The fruits of this tree are the macadamia nuts that are a part (or should be) of our diet.

Image – Oxfam

The macadamia nut has its roots in the rainforests of Australia, specifically in the north-eastern regions of Queensland and New South Wales. Indigenous Australians were the first to discover and consume these nuts, using them as a valuable food source and often trading them.

In the late 19th century, a botanist named Ferdinand von Mueller named the nut after his friend, Dr John Macadam. It wasn’t until the early 20th century that macadamia nuts started gaining international recognition. Macadamia trees were introduced to Hawaii in the 1880s, and they flourished in this tropical paradise.



Today, Australia and Hawaii remain large producers of macadamia nuts. But these nuts are also increasingly cultivated in other regions with suitable climates, such as the subtropical regions of South Africa. In fact, South Africa is today rivalling Australia as the major producer.

Macadamia nuts grow on trees. What we eat is the kernel of the nut, which has an outer husk and a very hard shell. Getting to the kernel is easier said than done. The macadamia is a very hard nut to crack.

Macadamia kernels, in shell, and fruit – Food for Mzanzi

Traditionally, the husk was removed, then the shell was bashed with a stone. This was a simple but tricky technology as an inexperienced and determined hand often bashed in the kernel as well. As technology advanced, the hammer came into use; but the nut had to be held with the other hand and any slip of the hammer could inflict serious injury on the holding hand.


Then came the vice. More control could be exercised with careful tightening of the vice, but this was a slow and laborious method. However, since we are currently in the technology era, there are specially designed machines that do the job nowadays – with appropriate application of artificial intelligence.

From 1 211 tonnes nut-in-shell in 1991 the South African harvest has grown to more than 60 000 tonnes in 2022. SAMAC (Macadamias South Africa) notes that “the total value of annual production has increased from R32 million in 1996 to approximately R5.1 billion in 2022”. Farmer’s Weekly reports that the SA “macadamia industry is expanding by over 3 000ha/year and the planted area has reached around 30 000ha”. This expansion is likely to be bolstered by growers in KwaZulu-Natal who are looking for alternatives to sugarcane after Tongaat Hulett went into business rescue in October 2022.

Why is the macadamia market growing? For a start, the nuts are delicious – by far my favourite nut. Secondly, they are packed with nutrients and many health benefits have popularly been claimed for them. Macadamia nuts are rich in monounsaturated fats, which have been shown to promote heart health by reducing cholesterol levels. They also contain omega-3 fatty acids, which further contribute to cardiovascular well-being. These nuts are also a good source of antioxidants like vitamin E, which help to protect the body against free radicals and oxidative stress; antioxidants play a crucial role in reducing the risk of chronic diseases, including certain types of cancer.

Macadamia nuts are a nutrient-dense food, providing essential vitamins and minerals such as magnesium, copper, manganese, and thiamine (vitamin B1). These nutrients are vital for overall health, supporting various bodily functions. Despite being high in calories, macadamia nuts can be a helpful addition to a weight management plan as their healthy fats and high fibre content contribute to a feeling of fullness, reducing the likelihood of overeating.

Despite being a superfood, macadamias occupy only 2% of the total nut market. If they are so delicious and so nutritious, the macadamia would be expected to have a higher market penetration. The simple answer is cost – the difficulty of getting to the nuts makes it expensive to produce. Could there be room for small-scale macadamia farmers to sell directly to the local market at lower than the export price? I really hope so.