"Ruby Tart" is another outstanding selection, with a similar vivid, dark red colouring, and large green leaves. . Easy to grow and disease free in a wide range of climates. It grows all year round and is a must have for any keen gardener. Growing rhubarb in New Zealand is very easy. Rhubarb is one of a small group of perennial vegetables. It grows best in partial shade in a cool to warm climate.