Definition - What does Chalk Soil mean?
Chalk soil is a soil that has a high alkalinity and pH due to the amount of lime and calcium carbonate in the soil. Chalk soil is typically not considered to be very fertile and can inhibit growth in grapevines, as the high alkalinity interferes with the uptake and processing of nutrients and energy.
WineFrog explains Chalk Soil
Chalk soils are stony, shallow, well-draining soils that are not known to be very fertile for traditional agriculture. Chalk soils are known as hard soils due to the high amounts of lime, calcium carbonate and even rocks found in the soil. Due to their hard stony texture, organic matter decomposes very quickly and is not held in the soil. Due to the high pH, chalk soils can lead to yellowed leaves and stunted growth in vines as the high pH inhibits the uptake of iron and manganese by the roots. However, many grape vines can grow quite well in managed chalk soil, including Chardonnay, Pinot Meunier and Pinot Noir that are grown in the chalk soils of the Champagne region of France.