In 1919 two brothers, Tinnie and Niels Momberg, bought Middelvlei and moved their families onto the farm. A year later the first wines were pressed, mainly fortified at that stage. Their two sons, Stiljan (quiet Jan) and his cousin, also Jan but called Jan Bek (because of his more outgoing personality), inherited the farm in 1960. In 1963 Stiljan bought his cousin's half share in the farm, to become sole proprietor. Jan Bek went on to buy nearby Neethlingshof Estate and subsequently entered politics.
Over the next thirty years, Stiljan set about establishing one of the model wine farms in the district. He upgraded the vineyards and by 1992 had replanted the entire 130 hectares under vine. Gradually the proportion of red plantings increased and today sits at 60% red (Pinotage, Cabernet Sauvignon, Shiraz and Merlot) and 40% white (Chardonnay and Sauvignon Blanc).
In the early 1970's Middelvlei became well known for its Pinotage and in the mid-1980's its Cabernet Sauvignon attracted considerable attention. Shiraz followed and in 1997 Middelvlei won the sought after General Jan Smuts Trophy for the best young wine in South Africa with their Shiraz. Middelvlei's pioneering Pinotage Merlot blend (Red Falcon Red) – the traditional Pinotage specialist was the first to combine South Africa's home-grown variety with what is one of the Bordeaux classics – made its first appearance in 1995. This was one year after the release of the only white, a unoaked Chardonnay.
The modern generation of Mombergs, brothers Tinnie and Ben, have learnt well from their father, Stiljan. Ever since he handed over the running of the farm to them in 1995, his quiet and kindly patriarchal influence has been felt, but, by then, most of the groundwork had been done. Stiljan had inculcated in them a strong work ethic and a culture for perfection and foresight in the vineyards and cellar. Ever mindful of the strong sense of tradition at Middelvlei Estate, Tinnie and Ben have blended modern winemaking and viticultural techniques with tried-and-tested methods, and, together with the marketing skills of Ben's wife, Jeanneret, have created a potent force on the Cape wine scene.
The estate covers 160 ha of which 130 are planted with vines. As an estate, all Middelvlei wines are made from their own grapes.