Is it cold hardy? Online information for the cold climate gardener

Just like you, Judy, “I like having an idea of whether [a plant] would turn to slime come April before I spend money on it.” I’m always on the lookout for sources of information that keep me from reinventing the wheel. Woody Landscape Plant Cold-Hardiness Ratings, Technical Bulletin #156 from the Maine Agricultural and Forest Experiment Station, is one of the first sources of information I found. UMaine maintains the Lyle E. Littlefield Ornamentals Trial Garden in Orono. According to the Introduction, “the site is in USDA hardiness zone 4a having suffered winter temperatures as low as -30 degrees F. three times in the last 6 years.” (This was published in 1994.) The plants are grown without winter protection except for mulch and are rated numerically to indicate their winter survival: 1= no damage whatsoever and 5=died. However, as Reeser C. Manley pointed out to me in an email dated 3/7/2001, “. . . in some cases only one to a few plants were tested. This is fine if they survive, but tells you nothing if they die since winter survival is a function of so many variables, freezing tolerance being only one.” True enough, but it’s a good place to start if you don’t have a clue as to what trees and shrubs will survive in your climate, and the woody plants are the most expensive. Best of all, the booklet is free for the downloading.