Tracey Rose and Moshekwa Langa are senior artists, which, I imagine, makes them sound like old fogeys from a forgotten art age. In a way they are. Both artists came to prominence during the heady period bracketing the short-lived Johannesburg Biennale, held in 1995 and 1997.Their radical practices, which embraced installation, film and performance without rejecting old-fashioned media, like drawing, ushered in new ideas about art in a reconstituted society.Success quickly followed. Both artists were picked up by the prestigious Goodman Gallery and began clocking air miles. But the vagrant carnival that is the "contemporary art scene" can be taxing.Rose had a public meltdown on a Cape Town stage in 2005. Two years later, she rankled art world mandarins with her antics (booze mixed with provocation) at the Global Feminisms exhibition at the Brooklyn Museum.This self-described "diva period" culminated in Rose being fired by the Goodman in 2008.Langa's journey has been no less tumultuous. Despite the support of numerous influential curators, including Okwui Enwezor, his career somehow got lost (booze and family trauma) just as Nicholas Hlobo's was taking off at the end of the last decade. Both these artists were born in 1975, Rose the year before.But this is a good news story. Langa's luminous debut solo exhibition in Cape Town with his new gallery, Stevenson, is a wonder. His painterly ink works, most of them pure abstractions, are a blaze of confident colour.It is spring again in Langa-land.Stevenson are ebullient, so much so they dedicated their entire booth at last week's Frieze Art Fair in New York to Langa. He is also currently exhibiting on Dak'Art 2016, the Senegalese biennale held every other year in Dakar.So, too, is Rose. Now reunited with her Goodman family, she is represented on curator Simon Njami's group show by a recording of a gonzo performance made in Belgium last year. Die Wit Man shows Rose in face paint walking across Brussels to a neo-Gothic church chanting the name of Congo's first democratically elected leader, Patrice Lumumba.Rose is clear about her reason for invoking Lumumba, who was assassinated by Belgian agents in 1961."It speaks to the Black Lives Matter movement, the Fees Must Fall movement and revolutionary black people taking a decisive stance."Rose's politically charged work was commissioned by Cameroonian curator Koyo Kouoh, whose career is on the rise. Kouoh is currently curating EVA International, Ireland's biennial of contemporary art. Rose has a work on this show too.And next month she has a project debuting on Unlimited at next month's Art Basel in Switzerland. It is full-blown summer again for Rose...