1975

Worst recorded drought and most of the Montana planting dies and the importance of irrigation was eventually recognised.

Auckland-based wine company Montana first planted Müller-Thurgau and cabernet sauvignon vines in the Wairau Valley, Marlborough, in August 1973. Most of these died in the summer drought that followed. 

The first vines were planted with much fanfare, but they failed miserably; a summer drought put an end to the fledgling vines. Undeterred, Yukich trialed more plantings, including hybrids and a fruit salad of vitis vinifera varieties. It was a happy accident that Sauvignon Blanc was chosen in 1975. The first Marlborough Sauvignon Blanc was released in 1979. At that time, only the most optimistic could predict that this sheep farming community’s future would change dramatically.

Source

MEX     23/08/13

https://teara.govt.nz/en/photograph/18351/planting-a-vineyard-in-marlborough-1973

https://vinous.com/articles/new-zealand-whites-the-great-divide-apr-2023