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Maryland's Geography and Climate
The Seventh State is home to approximately 13,000 farms which occupy 36% of the states total land area. Maryland wine, made with the grapes harvested from an estimated 430 acres of vineyards, flows through the states twenty wineries.

Maryland covers 12,303 square miles, making it the 42nd largest state. The Chesapeake Bay occupies 1,726 sq mi of this total, Chincoteague Bay covers 106 sq mi, other inland and tidal waterways comprise 597 sq mi, leaving a total land area of 9.874 sq mi. The state is divided into 23 counties, ranging in size from 219 sq mi (Calvert county) to 664 sq mi (Garrett county).

Because of Maryland's mid-latitude location, it enjoys a rather moderate climate, with an average temperature of 56 degrees (F). The Chesapeake Bay also adds a moderating effect, keeping both summer and winter temperatures from reaching extremes, although the two westernmost counties of Garrett and Allegany are prone to quite cold winter temps. The growing season averages 195 days, more than sufficient for most varieties of grapes.

Average rainfall is 42 inches which occurs mainly during the spring and late fall. Not only is this adequate for growing grapes, but the dry summer period increases sugar levels in the grape crop. Coupled with the moderate, and not excessive, summer temperatures, this region's climate is well suited for the production of high-quality grapes.

For a more detailed description of the climate of Maryland, see The Grape-Growing Climate of Maryland.

Maryland is comprised of five natural regions, transitioning gracefully from the Chesapeake Bay (sea level) to the Appalachian Mountains (3,360 ft. at the peak of Backbone Mountain). (Also see the Geologic Map of Maryland).

1. The Coastal Plain covers the eastern half of the state. This low, flat region is home to many rivers and streams. The north/south orientation of the Chesapeake Bay divides the plain into two parts, appropriately labeled the Eastern Shore and the Western Shore.

2. The Piedmont Plateau lies to the west of the Coastal Plain, and is separated from it by a line that runs roughly from the head of the Chesapeake Bay and travels southwest though Baltimore and the District of Columbia. The region has a gently rolling topography that includes the Frederick Valley, which is drained by the Monocacy River.

3. The Blue Ridge cuts across Maryland in a north-south direction along the Frederick-Washington county line. This region has the Catoctin Mountain at its eastern end, and South Mountain at its western end.

4. The Valley and Ridge region is in the narrowest portion of the state and is comprised of the Cumberland Valley, which is a part of the Great Appalachian Valley.

5. The Alleghany Plateau, part of the Alleghany Mountains, covers the westernmost part of the state and runs in a generally northeast/southwest direction. This region is home to Backbone Mountain, which at 3,360 feet is the highest point in the state.

(by Del Fanning, Department of Agronomy University of Maryland, reprinted from the Fall 1996 Grapevine).

Soils in the Coastal Plain vary largely in texture and in natural drainage class. The silty soils, many of which are in glacial age wind-deposited sediments generally have the highest natural water- holding capacities. Some soils in this region, particularly in Southern Maryland, have dense subsoil layers called 'fragipans', which restrict root and water Penetration.

Piedmont region soils vary depending upon the kind of rock formations from which they are developed. Weathering in the Piedmont is often very deep and this deeply weathered zone, when it doesn't show much evidence of disturbance other than from chemical weathering, is called 'saprolite' (rotten rock) by soil scientists and geologists. Fragments of hard, relatively unweathered rocks called 'channers' (gravel size), flagstones or stones depending on their size may remain in the weathered zone. Iron-bearing, basic or mafic rocks tend to weather to give redder soils with higher clay content than more acidic or sialic rocks.

Soils in much of the Appalachian Mountain region (the Blue Ridge, Valley and Ridge, and the Appalacian Plateau) of the state are formed from sedimentary rocks of various kinds, sandstones, shales and limestones with the general pattern of the limestone soils more in the bigger valleys (eg, around Frederick and Hagerstown), with the soils from shales and sandstones on the higher terrain. Soils on the side slopes are commonly in colluvium both in the Piedmont and Mountain provinces. This is material that has moved downslope from higher places by gravity. This appears to have taken place more in the geologic past when the region was colder by a geologic processes called 'solifluction' -- a process that continues to take place in tundra regions of today.

Maryland Grape Growers Association ©2017