A unique phenomenon happens at Iona Wines. The combination of the short distance from the freezing Atlantic Ocean and the rapid increase in altitude causes the prevailing summer South East wind to roll across the vines, forming misty clouds that blanket the farm on warm days.

Groote Post is situated 7km from the cold Atlantic. The cooling effect of the ocean creates an ideal climate in which vines flourish, providing a longer growing season with greater build-up of flavours in the grapes.