Hardiness

Plant hardiness is based on USDA Plant Hardiness Zones. These are based on the lowest annual low temperature in the location. In general hardiness zones progress in 10 degree Fahrenheit increments between zones, with a 5-degree increment within a zone. The coldest zone is zone 1, with winter low temperatures of -50F or colder. Around Interior Alaska zone 1 translates to all the low-lying areas. Higher areas are warmer, some are zone 2, the highest perhaps zone 3. Hardiness zones pertinent to Fairbanks include:

Zone 1 - winter low temperature of -50F or colder

Zone 2a - winter low temperature of -45 to -50F

Zone 2b - winter low temperature of -40 to -45F

Zone 3a - winter low temperature of -35 to -40F

Zone 3b - winter low temperature of -30 to -35F

In general apples will grow in warmer zones than they are rated to, so if you are fortunate to live in a zone 3 location you can grow apples hardy to colder zones. If on the other hand you live in zone 1 the other less hardy apples will probably not make it in your location. The apple varieties listed 0n this site break down as follows (with my personal experience with a zone 2 orchard):

Zone 1

Dawn, Dolgo, Heyer 12, Heyer 20, Noret, Norhey, Prairie Sun, Rescue, Shafer, Trailman. (September Ruby, Clair 4 and Rosthern 18 are possibly zone 1 apples too)

Zone 2

Advance, Kerr, Norcue, Norda, Parkland, Patterson, Renown, Rosthern 18, September Ruby, Sunnybrook, Westland, Y6211, Lee 31, Clair 4, Garland, Clair 9, Altai Mountain, Cinese Golden Early

Zone 3

Adanac, Carroll, Norkent, Norland, Norson (these latter 3 have repeatedly died, or died back hard each winter, so I'm about to give up on them, one last try on Baccata rootstock to see if that helps, Norkent especially won't stop growing before winter sets in). Currently Norkent has made it a couple of winters on Baccata without damage. Fingers Crossed

Unknown

Lee 17, Lee 27, 21-61-29, Prairie Sensation, Redstar and 4-15-50 (Nicky), and are at least hardy to zone 3, as our orchard is at least that cold, they may be hardier, but I have not found any information beyond our orchard.

Simonet, Yellow Transparent and Zestar died in our location, after a valiant struggle. I don't think they are hardy enough in my orchard, which has been borderline zone 2 to zone 3 since the trees have been in place. Maybe I'll try again after some experimentation with rootstock.

These varieties have taken frosts to 28F with no damage to the fruit. Kerr has taken to 25 with no damage.