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Spilling the Tea on South African Herbal Teas

Grounded Ingredients offers three indigenous herbal teas endemic to South Africa’s Cape Floristic Region. Though all three can only be grown and produced here, they have distinct properties and flavours. Below we explore the different methods of production, varying health benefits and unique flavours of rooibos, honeybush and buchu. 

by Elzanne Singels

16 February 2022

Cultivated rooibos (Aspalathus linearis) in flower. Credit: Elzanne Singels

TThe Cape Floristic Region (CFR) is a small biogeographical area at the southwestern tip of the African continent. Its geographic footprint may be small, but it is a hotspot of diversity: the region has the world's highest rate of plant endemism, or plant species that occur nowhere else on Earth. The utterly unique flora here is called fynbos, from the Dutch "fine shrubbery." Apart from its unparalleled plant diversity, the CFR also has a rich human history, with hunter-gatherers living in this region for thousands of years. These indigenous groups, the Khoi-khoin and San, discovered the myriad uses of fynbos plants.

Rooibos, honeybush and buchu are three species of fynbos plants that the Khoi-khoin and San used for their powerful health benefits. All three were commercialised in the 20th century, and they are now exported all over the world for use in the tea, culinary, cosmetic and pharmaceutical industries. So what is the difference between these three teas from the Cape Floristic Region? We present a brief overview of the production, health benefits, and distinctive flavour profiles for each. 

Production areas of Rooibos, Honeybush and Buchu. 1-4) Different species of Honeybush; 5) Aspalathus linearis (Rooibos); 6) Agathosma betulina (Buchu). Adapted from Joubert et al., 2008.

Rooibos

Rooibos, meaning "red bush" in Afrikaans, is the most famous South African herbal tea. Rooibos (Aspalathus linearis) is a member of the pea family, with a very narrow natural distribution in two main areas in the north of the Cape Floristic Region: the Cederberg and Namaqualand. Rooibos is a perennial plant of an olive-green colour, with upright shoots and fine, needle-like leaves. It bears small, yellow, pea-like flowers.

Production

Traditionally, rooibos was wild harvested and wild A. linearis populations were sufficient to satisfy local demand. In emerging ingredient markets, this phase is known as the ‘cottage industry phase’. As the demand for rooibos started to outweigh the available wild supply in the early 20th century, cultivation was trialled. There was a big push, subsidised by the South African government, to commercialise rooibos and promote it abroad. This effort was very effective at growing the market for rooibos, and it is now cultivated successfully throughout the West Coast of South Africa. Approximately 6 500 tons of rooibos are now exported to thirty countries each year, although the industry has the capacity, in a good year, to produce 18 000 tons (SARC, 2018). Apart from the international market, the local market for rooibos is also sizable, and it is the most popular herbal tea among South Africans.

Cultivated rooibos (Aspalathus linearis) in flower. Credit: Elzanne Singels

Rooibos is farmed in the northwestern corner of the Cape Floristic Region, on typical fynbos soils which are nutrient poor and acidic. Because it is naturally adapted to local, semi-arid conditions, it can be cultivated without irrigation. Seedlings have a lifespan of about five years, after which they are removed or tilled into the soil for the next crop. All pea plants have the amazing capability to fix nitrogen (with the help of microbes!) from available nitrogen in the air, so rooibos cultivation does not require extra inputs like fertiliser, as it collects the nutrients it needs from thin air.

Harvesting occurs in December and January, the height of the South African summer, on days when the ambient temperature is 35° Celsius (95° Fahrenheit) or higher. Rooibos is harvested with a sickle, then transported to the processing facility where it is chopped, spread onto cement drying slabs, sprayed with water and allowed to oxidise. During oxidation, the plant matter transforms from bright green to the iconic red for which the tea is named ("rooi" means red in Afrikaans). When sufficient oxidation has taken place, the tea is dried, sterilised, packed and exported all over the world.

In 2021, rooibos became the first food in Africa to be registered on the Protected Designation of Origin (PDO) list, joining the ranks of Champagne and other products unique to their production region. This means that rooibos cannot be farmed, processed or produced anywhere but in South Africa. Other uniquely African ingredients like honeybush and buchu should also enjoy the protection of this designation in the future, but to feature on this list requires very concerted efforts. For now, the size of the rooibos industry justifies the effort.

The brew

Rooibos tea has a beautiful amber-red hue. It is naturally caffeine-free, low in tannins and packed with antioxidants. It can be brewed as a loose leaf or bagged tea, and should be steeped for at least three minutes. Describing the aroma and taste of South African indigenous teas is difficult, because there is simply nothing else on earth that compares. Rooibos is smooth and gentle, with a subtle sweetness and an earthy, nutty taste. Its subtlety makes it an excellent base for blending with other flavours, and it pairs well with dried fruits, spices and vanilla.

If you ever have the opportunity to visit the Cape Floristic Region and walk in the aromatic fynbos vegetation, you will recognise rooibos's quintessentially fynbos aroma and taste. There is nothing else like it!

Oxidising rooibos at left and the typical striking red colour of brewed rooibos at right. Credit: left Elzanne Singels, right Stephanie Gschwandtner

Health Benefits

Hundreds of academic studies have investigated the health benefits of rooibos. A recent review of the tea's health-promoting properties found that rooibos “displayed potent anti-inflammatory, antioxidant, redox modulating, anti-diabetic, anti-cancer, cardiometabolic support and organ supportive potential” (Naeem & Marnewick, 2021). The review also found that rooibos can potentially play a role in modulating the risk of some of the comorbidities associated with COVID-19, promoting general health during infections (Naeem & Marnewick, 2021). A recent study found that green rooibos, or rooibos that has not been oxidised, can reduce anxiety (Lopez et al., 2022). There are no detrimental effects of drinking rooibos – drink all you like without the risk of overdoing it! It is even safe to drink while pregnant and breast-feeding.

Honeybush

Honeybush is the common name for the Cyclopia genus, consisting of twenty-three species also in the pea family. Honeybush tea has been used for thousands of years by the indigenous people of the Cape Floristic Region, who used it to treat various respiratory illnesses from asthma to tuberculosis and pneumonia, and to improve immune function for colds and flus (Bowie, 1830; Skead, 2009; Thunberg, 1795). Honeybush species are perennial shrubs with very different leaf morphology between species. All species bear large, yellow pea-like flowers in spring and summer – entire mountain sides can be washed in yellow during this time.

Two morphologically different honeybush species in the Langkloof Valley. Credit: Elzanne Singels

Production

Honeybush species are naturally adapted to the nutrient poor, acidic soils typical of fynbos. Wild populations could be harvested sustainably to satisfy demand during the cottage industry phase of the industry, but as demand for honeybush increased in recent years (with a peak of more than 600 tons annually), pressure on wild populations became excessive. Consequently, various honeybush species are at risk of extinction (McGregor, 2017). 

To alleviate harvesting pressure on wild populations, many farmers started to cultivate honeybush. The species which are most commonly wild harvested and cultivated are Cyclopia genistoides, C. sessilifolia, C. subternata, C. intermedia (Joubert et al., 2011). But the demand for honeybush has fluctuated sharply in the past ten years. Currently, the supply of wild honeybush outweighs the total demand for honeybush tea, and there has been a sharp decrease in the amount of honeybush produced annually, down to less than 300 tons (McGregor, 2017). This lower demand means that the demand for honeybush can be met exclusively by sustainably wild harvesting. Many farmers are now opting to remove their cultivated honeybush, due to the opportunity cost associated with cultivating the tea instead of a different crop.

But when the market picks up again, overharvesting of wild honeybush could again cause risk of extinction to vulnerable species. Fluctuating demand can halt the progress of a young industry such as this, and makes the transition from exclusively wild harvesting to sustainable cultivation difficult.

The harvesting and processing of honeybush tea is similar to rooibos, though the oxidation process occurs in steam tanks rather than open-air oxidation. Because the processing of honeybush has a profound effect on the resulting quality and flavour profile of the tea, processing needs to be executed in a very controlled environment (Bergh et al., 2017).

The brew

Similar to rooibos, honeybush can be brewed as looseleaf or bagged tea, but it should be steeped a bit longer – at least five minutes – to bring out its depth of flavour. It is low in tannins and caffeine-free, and cannot be over-steeped. It produces a lovely peach-coloured tea, often with a floral and honey aroma. Each batch of tea has a distinct flavour profile, however, influenced greatly by the cultivation and processing methods the tea has been subject to (Theron et al., 2014).

As the honeybush industry is relatively young, stakeholders and researchers are still getting to grips with the amazing diversity of flavours to be found in honeybush tea. Many compounds which contribute to the rich aroma of honeybush tea have been identified. The most common aromas identified are floral, including rose geranium, rose perfume, fynbos-floral; plant-like, such as fynbos, green grass, pine, woodiness and hay; fruity, such as apricot, apple, lemon and raisins; sweet, such as honey, caramel; and spicy or nutty aromas (du Preez et al., 2020). When processing is done correctly, this product has enormous potential. Like rooibos, honeybush also makes an excellent base for blending with other flavours: the wide array of naturally occurring aromas in honeybush can enhance added ingredients such as mango, vanilla, hibiscus, giving it dynamic appeal for tea blenders. 

Honeybush blends of varying hues. Credit: left Elzanne Singles, right Stephanie Gschwandtner

Health Benefits

Studies confirm the health benefits for which honeybush was traditionally used. The plant contains a hyper-diverse range of phenolic, antioxidant, anti-microbial and anti-carcinogenic compounds, which cause these beneficial effects (De Beer et al., 2012; De Nysschen et al., 1996). While the concentration and combination of compounds are unique between species, the following dominant compounds are found in almost all of the twenty-three Cyclopia species: Xanthones (Mangiferin and Isomangiferin), flavanones (Hesperidin, Eriocitrin) and Isosakuranetin (De Nysschen et al., 1996). 

As with rooibos, honeybush has a supportive function for the respiratory system and, due to the high hesperidin content of the tea, it is a promising prophylaxis in the treatment of COVID-19 (Meneguzzo et al., 2020). There are no detrimental effects to drinking honeybush – you can enjoy as much as you like, even if you are pregnant or breastfeeding. 

Buchu

Buchu is the common name for many different fragrant species in the Citrus family that occur in the Cape Floristic Region. Generally, however, buchu refers to Agathosma betulina. A. betulina is a perennial shrub with small spear-shaped leaves, the underside of which are scattered with visible oil glands. It bears attractive star-like flowers ranging from pink to white. Buchu has a narrow native range in the Cederberg mountains, which extends down to the Cape Winelands to the south. It grows on the wet, southern-facing slopes, often below seasonal waterfalls – an idyllic scene to find yourself in as a plant in a semi-arid region.

Buchu is an important plant to the indigenous San and Khoi-khoin cultures of South Africa and has always been used to treat a wide range of conditions. It was dried, powdered, combined with sheep fat and applied to the skin for multiple reasons: as protection from the sun, for its anti-fungal and antibacterial properties, and as a perfume (Bowie, 1830; Skead, 2009; Thunberg, 1795). A tonic was - and still is - produced from the plant, which was applied as antispasmodic, antipyretic, as a cough remedy, to treat colds and flus, and for kidney support and infections (Moolla & Wiljoen, 2008). The reputation of buchu as a powerful medicine was spread to Europe during colonisation of the Cape, and it has been exported since the 1600s (Watt & Breyer-Brandwijk, 1962).

Cultivated buchu (Agathosma betulina) in flower. Credit: Skimmelberg

Production

Buchu undoubtedly ranks amongst South Africa’s most important medicinal plants and export products (Moolla & Viljoen, 2008). The international market for essential oil produced from A. betulina spiked in the 1960s, precipitating the need to farm buchu to increase production (Muller, 2015). But the rate of buchu production mirrors the trend described for honeybush: cultivation expands when demand for the product is high; when demand plummets, cultivated plants are removed to make space for more profitable crops (Muller, 2015). This pattern is further compounded by the fact that buchu is tricky to cultivate, requiring specific conditions that mimic its natural microhabitat. However, once a buchu field is established, the plants can live for sixty years and have relatively high yields for that duration. 

Buchu is harvested once a year. About 30% of new growth can be harvested, without affecting the long-term survival of the plant. Most cultivated buchu is used in the production of essential oil, which is of very high value, while a small amount is used in leaf form for the tea industry. The herbal tea produced from buchu is not oxidised, but simply dried. 

The brew

Buchu tea consists of whole leaves and is generally steeped loose for three minutes. Because of its potent health benefits and strong flavour, it is frequently blended in small quantities into other teas. When steeped on its own, it creates a lightly green-coloured, clear tea. Buchu leaves contain many volatile compounds, which are extracted into a high-value essential oil frequently used as a natural alternative for blackcurrant or berry flavours in the food, beverage and perfume industries. If you have ever had a blackcurrant flavoured drink, medicine or sweet, you have likely tasted buchu! It’s flavour is strongly medicinal, fruity and fresh.

An established buchu field at left and the light-green of brewed buchu at right. Credit: left Elzanne Singels, right Stephanie Gschwandtner

Health Benefits

Many studies confirm the health benefits for which buchu was traditionally used (Moolla & Viljoen, 2008). Like rooibos and honeybush, buchu is filled with potent antioxidant and anti-inflammatory compounds, which have been found to regulate blood sugar levels and confer anti-diabetic and anti-obesity effects (Moolla & Viljoen., 2008). Buchu has also been found to ease hypertension, which makes it good for heart health (Huisamen et al., 2019). It is also a diuretic, which makes it useful in the treatment of bladder and kidney infections.

Buchu is a powerful medicine, and like most medicines its effect depends on the dose administered. Because of this, there are levels of buchu intake that can have detrimental effects. Pregnant and breastfeeding women are advised to avoid buchu products. Due to its anti-clotting effects, people with bleeding disorders or those scheduled to undergo surgery should also avoid it. Extremely high doses of buchu intake can potentially cause liver damage. Normal food-intake amounts of buchu are, however, harmless, and will bestow the beneficial properties of the plant. In tea form, a couple of cups a day is completely safe.

Conclusion

The Cape Floristic Region is a treasure trove of unique plants, with an extremely high concentration of aromatic species (Moolla & Viljoen, 2008). Rooibos, honeybush and buchu are just a few of the potential herbal teas contained in the biodiversity of the region. Moreover, their applications are certainly not limited to tea. These plants have been used to produce all kinds of beverages (from kombucha to tonics, sodas, and iced teas, etc.), and they have many uses in the pharmaceutical and cosmetic industries.

Cultivated rooibos fields in the distance. The mountain slopes of Namaqualand and the Cederberg are the natural habitat of rooibos. Credit: Elzanne Singels

Rooibos is by far the most advanced of the three South African herbal tea industries, having benefited from a number of favourable factors that bolstered the industry. Buchu and honeybush are second runners, but there are potentially hundreds of other plant-derived ingredients that have not yet been able to overcome the obstacles facing novel ingredient industries. In our own work with honeybush, we have seen how the commercialisation of ingredients can have many negative impacts on the environment and on the custodians of traditional knowledge around a specific's plant use. However, there are methods that can be employed to commercialise novel ingredients in the right way

Most novel ingredients can be sustainably wild harvested exclusively throughout the cottage industry phase, if thorough sustainable methodology is used. But for industries to grow out of this phase, there has to be a focus on scaling through cultivation. If regenerative methods of cultivation are used, the environmental impact of the industry could even be beneficial. Equally important is the equitable development of novel ingredient industries – a big topic for a future blog. 

Although these indigenous herbal teas share origins in the Cape Floristic Region, they are each unique. If you are looking for a diversity of flavours and stories in your teas, you had better try all three. There is nothing in the world that tastes like fynbos, except fynbos. 

Get your fynbos herbal tea fix here >>

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