Noticed the bees working around the flower pots on our front stoop, and they weren't interested in the flowers as much as they were focused on the droplets and small puddles of water in the pots. Apparently they're thirsty.
I put out a shallow bowl with water near the hive to give them another drinking source. Filled the bowl with some extra crushed stone we had laying around to give the bees some surface area to land on.