When I popped into Sainsbury's the other day, I noticed they had packets of seeds.
They have put a sign on the packet to say its Bee friendly.
I bought 3 packets to scatter over the grass in the drive way. You don't have to have a garden to scatter the seeds.
Bee attracting flower seeds include Marigold, Lace Phacelia, Starflowers, Cornflower and Dill.