I have two hives in southern Maine that are overwintering well and I'd like to make a split off each this spring. During a quick inspection last weekend I noticed one hive has a small patch of brood while the other hive's queen hasn't started laying yet. Both hives have some honey in reserve plus a candy board on top and have what appear to be healthy populations.

My question is, when should I start feeding the hives pollen substitute to help them build up their numbers? Dandelion bloom in my area is usually around the first week of May.

Also, should I start feeding sugar syrup if I want to stimulate brood rearing, or is the candy board sufficient for now?