Like someone said in another thread, keep check on the stores. More bees starve between now and when the first good flow comes than during the winter. Rearing brood takes its toll on stores.
If you haven't done so already, make a small journal on the time different things bloom.
I know I want my colonies to be ready for the big one around the 20th of April. Tulip Popular, lapping over with Persimmons, honey locust, then blackberries. Then it is nip and tuck till the Kudzu blooms. :)doak