Cape sorrel are such a common weed in gardens that one rarely ever stop to notice it. As kids, we collected the flowers with stems intact and chewed on them for their pleasant sour taste. The yellow flowers light up in the sunlight and close at night to reopen again, once in the sun's rays. Cape sorrel is also very commonly used in Waterblommetjiebredie, a culinary dish in South Africa. Cape sorrel is clasified as an invasive species in South Africa and can be very difficult to eliminate if it's spread across a large area.