Uses

Through the 17th and 18th centuries, European travellers and botanists visiting the Cederberg region in South Africa commented on the profusion of "good plants" for curative purposes. In 1772, Swedish naturalist Carl Thunberg noted that "the country people made tea" from a plant related to rooibos or redbush.
Traditionally, the local people would climb the mountains and cut the fine needle-like leaves from wild rooibos plants. They then rolled the bunches of leaves into hessian bags and brought them down the steep slopes on the backs of donkeys. The leaves were then chopped with axes and bruised with hammers, before being left to dry in the sun.

In South Africa it is common to prepare rooibos tea in the same manner as black tea, and add milk and sugar to taste. Other methods include a slice of lemon and using honey instead of sugar to sweeten.
Several coffee shops in South Africa have recently begun to sell "red espresso", which is concentrated rooibos served and presented in the style of ordinary espresso. This has given rise to rooibos-based variations of coffee drinks such as red lattes and red cappuccinos. Iced tea made from rooibos has recently been introduced in South Africa, Australia, and in the United States. A variant of a London Fog, known as a Cape Town Fog, can also be made using Rooibos steeped in steamed milk with vanilla syrup.

Rooibos is grown only in a small area in the region of the Western Cape province of South Africa.Generally, the leaves are oxidized, a process often, inaccurately, referred to as fermentation by analogy with tea-processing terminology. This process produces the distinctive reddish-brown colour of rooibos and enhances the flavour. Unoxidized "green" rooibos is also produced, but the more demanding production process for green rooibos (similar to the method by which green tea is produced) makes it more expensive than traditional rooibos. It carries a malty and slightly grassy flavour somewhat different from its red counterpart.

Rooibos is becoming more popular in Western countries, particularly among health-conscious consumers, due to its high level of antioxidants such as aspalathin and nothofagin, its lack of caffeine, and its low tannin levels compared to fully oxidized black tea or unoxidized green tea leaves. Rooibos also contains a number of phenolic compounds, including flavanols, flavones, flavanones, and dihydrochalcones.
Rooibos is purported to assist with nervous tension, allergies and digestive problems. Rooibos tea has been shown to inhibit in vitro activity of xanthine oxidase, yet an in vivo study has not been conducted. Xanthine oxidase (XO) plays a role in conversion of purine to uric acid in humans and reducing the activity of XO could limit uric acid production, which would aid in treatment of gout.

Although human studies of rooibos are scarce in scientific literature, animal studies suggest it has potent antioxidant, immune-modulating and chemopreventive effects. In addition, no adverse side effects of consuming rooibos tea have been documented.
It is often claimed that "Green" rooibos (see above) has a higher antioxidant capacity than fully oxidized rooibos. However, one study, using two different ways of measuring antioxidant activity, found conflicting data, with green rooibos showing more activity under one measure, and less activity using the other. The study also found conflicting data when comparing both forms of rooibos to black, green, and oolong tea, although it consistently found both forms to have less activity than green tea.