The subject of this "teas-day" isn't actually a tea in the truest meaning of the word. Rooibos is made from the oxidised leaves of a South Africa legume and is often called red tea due to its distinctive red colouring.
Unlike tea, Rooibos is caffeine free and almost impossible to overbrew. What came as a surprise is that you can also get Green Rooibos.
Green Rooibos like Green Tea is unoxidised which means it is lower in tannins. Once brewed you can see the difference even more clearly.
I found the green to have a more pronounced grassy flavour but seemed fresher due to the lower tannin level. They both have sweet notes but I would say the regular Rooibos edges ahead on sweetness - it also has a somewhat richer flavour.