When Grant moved the hives to the alfalfa fields it became awfully quiet around here. I was very concerned for several weeks that he would have to bring back a hive to ensure decent pollination because the bees were no where to be seen. It would be pretty embarrassing to have beekeepers have to hand pollinate their veggies!
Last year, I planted bachelor's buttons, as well as lots of annual poppies, and they reseeded all over the garden. Of course, since it's against my nature to pull anything that's durable enough to come back we have flowers all over the garden. It's been an enormous blessing because not only are they gorgeous, they're a veritable buffet for the bees. When we go out in the morning the area is literally buzzing with the hard working girls, and they're obviously hitting the veggies, too, since there are plenty of squash and tomatoes setting.
A friend of mine in town is definitely having an issue with the lack of bees, although they have hives just down the road. She's been using the paint brush on the squash blossoms. Where she's done it, they produce. But the ones she missed are dying quickly. There are too many other fun things to do in the summer than to play worker bee at home! So, plant those flowers to bring in the bees!