IN THE NORTHEAST

by Walter L. Stirm.

Walter L. Stirm is Advisory Agricultural Meteorologist, National Weather Service, West Lafayette, Ind.

Gardening can be successful in every State of the Northeast region but is dependent on the climate. The region consists of Iowa and Missouri, and States east of the Mississippi and from the Canadian border southward to and including Kentucky and Virginia. Two basic climatic areas in this humid region are one with small temperature changes and another with moderate changes.

The small temperature change area comprises primarily all the Northeast region north of 40 latitude. This is a cold climate varying from hot summers (average above 71.6 F) and cool long winters as in the New England States. The area is forested and has frozen soil and snow cover for several months in winter. Rainfall is adequate in all seasons.

The moderate temperature change area comprises most of Illinois, Indiana, Kentucky, Ohio and the mid-Atlantic States. The climate is warm and rainy. There is no distinct dry season. Winters are cool and short, with frozen soil and snow cover a month or less in duration. Weather in the summer growing season varies from hot in much of the area to cool long summers in the Appalachian Highlands. Rainfall is adequate and sometimes more than needed during the growing period. A marine-like climate exists at times along the Atlantic Seaboard States.

Geographic features are favorable for gardening throughout the Northeast. Numerous streams provide a good drainage system. Swamps and high terrain areas are minimal in extent. Elevations range from 200 to 800 feet above sea level in the eastern Great Plains and Great Lakes area, to 0 to 200 feet above sea level in the middle and north Atlantic States. Appalachian Highlands range from 2,000 to 4,000 feet above sea level and are 10 to 12 F cooler in summer because of the elevation. Mountain valleys and high plateaus are usually problem areas in the highlands due to cold air drainage and strong winds. Western slopes of the Appalachians are also cooler and cloudier during spring.

Areas within 20 to 30 miles of the south and east shores of the major Great Lakes have extensive moderation in temperature and precipitation conditions during all seasons. Numerous lakes in this area provide some moderation effect. Spring and summer rainfall is diminished, but rainfall increases in fall and winter. Temperatures are cooler for a longer time in spring but warmth is extended in autumn.

Large fertile flood plains are characteristic of river drainage systems throughout the Northeast. These areas have more water than needed in late winter and spring.

Temperature and rainfall are important to success in gardening through all of the Northeast. Average temperature and precipitation data are given in the table for representative cities in each State of the region. Average monthly temperatures are used as a guide in planting and for determining length of the growing season. The beginning and end of the growing season for cool season crops closely follows the time when average temperatures warm to 40 F in spring and cool to 40 in fall. For warm season crops an average temperature near 50 is used.