The Auckland wine region, surrounding the country's largest city by the same name, is home to some of the largest wine producers in New Zealand although a lot of the grapes are sourced from the other parts of the country. This is because of the rather humid climate, both due to the coastal influence and high rainfall, which makes grape growing a challenge. But the region also experiences enough warm temperatures during the growing season which assists in the production of some high quality red wines, especially from Cabernet Sauvignon and Merlot.