It's my first winter as backyard beekeeper in zone 5b. I've read it's good to add a pollen patty at this critical juncture, so bees won't starve. Haven't opened hive all winter - too cold! But can hear them buzzing and have seen cleansing flight activity when visiting the hive (almost daily). When can I think about opening the hive to add a pollen patty or two? Does it have to be a 55 or plus degree day for a quick pollen patty drop? Any tips on how/when to do this is much appreciated. (Fingers crossed). Thanks!