Strawberry Social - Hardiness Zones

Celsius	Zone	Fahrenheit
Below -45.6 C	1	Below -50 F
-42.8 to -45.5 C	2a	-50 to -45 F
-40.0 to -42.7 C	2b	-45 to -40 F
-37.3 to -39.9 C	3a	-40 to -35 F
-34.5 to -37.2 C	3b	-35 to -30 F
-31.7 to -34.4 C	4a	-30 to -25 F
-28.9 to -31.6 C	4b	-25 to -20 F
-26.2 to -28.8 C	5a	-20 to -15 F
-23.4 to -26.1 C	5b	-15 to -10 F
-20.6 to -23.3 C	6a	-10 to -5 F
-17.8 to -20.5 C	6b	-5 to 0 F
-15.0 to -17.7 C	7a	0 to 5 F
-12.3 to -14.9 C	7b	5 to 10 F
-9.5 to -12.2 C	8a	10 to 15 F
-6.7 to -9.4 C	8b	15 to 20 F
-3.9 to -6.6 C	9a	20 to 25 F
-1.2 to -3.8 C	9b	25 to 30 F
1.6 to -1.1 C	10a	30 to 35 F
4.4 to 1.7 C	10b	35 to 40 F
above 4.5 C	11	above 40 F

Survival of plants is affected by many factors in addition to low winter temperature "zones":

freeze-thaw cycles during the winter often cause more damage than consistent cold temperatures.
snow cover has an insulating effect on plants: lack of snow cover can result in damage.
sun scald in late winter can crack the bark of many plants, especially trees, and will cause browning on cedars and junipers
late spring frosts can damage many plants, especially those that tend to put out buds early in the spring (e.g., apricots)
exposure to strong winds will kill some plants and cause unsightly discolouration on others
frost in low-lying areas can delay the onset of growth in the spring: for example, this nursery in spring is typically 2-4 C colder than the fields 50 meters away.
road salt and pollutants can have a major effect on winter survival: some trees and shrubs are very tolerant, while others (such as many cedars) will succumb to salt spray even during mild winters.

With so many factors affecting how well plants thrive in our climate, it’s difficult to specify exactly how a particular plant will do in a specific planting site. The "zone number" is a good general guide to hardiness, but if you have questions about a particularly difficult site, it's best to talk to a professional.