When to start feeding sugar water in the spring?

[Salmo]

Good evening everyone,

I'm about 3/4 of the way through my first year keeping bees, located in Nova Scotia.  We've had a fairly mild winter and on warm days, have seen bees outside the hive, so optimistic they will survive until spring.

My question, when should I start feeding them sugar water?  This far north, do you typically wait and make a judgement call based on avoid freezing temperatures ?

Any advise, rules of thumb and/or recommendations would be greatly appreciated.

Thanks Randall

[Rugerbob]

Middle of March to latter part of April, all depends on average temp.

I feed sugar cakes until temp are averaging 10C.

Bob 

[apisbees]

Go by hive weight lift the back of the hive and if very light then feed. syrup if it is warm enough, fondant blocks of frames of honey if it is still to cool for syrup consumption.