Long, gentle, mostly east-facing slopes ensure early exposure to the sun during the growing season. This results in early bud burst, most notably in the southern area of the appellation. The east-facing slopes provide excellent sunlight exposure to the vines and, like south-facing slopes create warm conditions for berry maturation. These conditions make the Niagara River appellation a favoured place to grow more tender varieties, which thrive in the sunlight and long growing season.
The Niagara River appellation is characterized by east facing slopes and the effect of the mighty Niagara River. Together they influence the microclimate and play an important role in developing this appellation's distinct and crisp wines.
The soils of this appellation have developed on the bedrock of the Queenstown Formation, a red shale with high silt and clay content. With its proximity to the river, this appellation shows significant soil variation along its lengths, specifically in terms of drainage. In the south, sub-soils are well drained and have medium to low water-holding capacities, favouring dry conditions later in the season. These conditions have a positive effect on grape quality, encouraging vines to grow deep, wide root systems, and devote energy to fruit production. In the north, sub-soils tend to be slightly less well drained and have a relatively high water-holding capacity, providing an advantage in particularly dry seasons.
The climate of this appellation is quite variable north to south due to the changing proximity to Lake Ontario. The river's flow creates air convection currents which moderate temperatures and draw cold air away from vineyards and into the river gorge. For vineyards near to the river, these air currents ward off early spring and late fall frosts, and support an extended growing season. To the north, breezes from Lake Ontario provide a reliable and widely distributed moderating effect on temperatures throughout the seasons.