Answer: It looks like you live right on the edge of <a href="http://www.garden.org/b2b/zipzone/index.asp"target="new">USDA Hardiness Zones</a> 5 and 6 where the annual average minimum temperature is -10<font size="-3"><sup>o</sup></font> to -15<font size="-3"><sup>o</sup></font>F. Remember this isn't an exact science; use this information as a starting point.
For instance, if you're selecting long-lived trees and shrubs, be conservative, assume you're a zone 5 and select plants accordingly. But with shorter-lived plants or whenever you feel safe being experimental, try some zone 6 plants.
Also check the <a href="http://www.garden.org/regional/report.taf?regionid=13"target="new">National Gardening Zone, Middle Atlantic region</a>. Over time you'll see here the kinds of plants you can grow, and other details about your region.
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