Spring Brood build Up Starts
As I write this we just celebrated “Presidents Day” (February 18, 2019). Between now (February 25th and the First of March our bees will start to find pollen on the days it warms up enough for the bees to break cluster and go outside for a cleansing flight and to start looking for pollen. Any time after the winter solstice if the temperatures are milder and pollen is able to be found the bees will begin to start brood rearing. Slowly at first. They will find pollen (white and gray in color) on willows, some varieties of trees i.e. cottonwood, quaken aspen (In our part of the world on the 41 Latitude in Utah. This can vary some depending where you live and your climate). When they start bringing back pollen to the hive and the days are getting longer each day. The bees will start the brooding up process in preparation for the Spring bloom that will begin the first of part of April (in Northern Utah). It takes the bees 21 days from when the queen starts lays eggs before new emerging bees will be present and hive growth will begin.
Supplemental feeding to support early brood build up
The bees left on their own will brood up only as fast as they are finding pollen to support the brood they are trying to raise. The Temperature will go from an average of 70 degrees (F) before this build up starts to a constant 92-93 degrees (f) as the brood nest enlarges in the brood up period. It is in the last month before Spring is in full bloom that hives can starve to death. You need to verify they still have plenty of food to sustain the higher heat level in the hive. They can consume almost as much in March as they did the rest of the Winter combined, depending on how long your winter is in your area.
In my hives I start feeding liquid syrup and pollen substitute patties. To support as quick of a brood build up as they are capable of. The only caution I give is if you choose to supplemental feed at this time. You can’t stop until there are abundant sources of pollen and nectar outside. (The Consequence of stopping before there is amble outside sources will leave the hive worse off than if you’d never helped them.) Swarming conditions can be reached a little earlier because of earlier hive build up. So, keep an eye on your hive and do swarm control a week before swarming begins in your area.