Black-eyed Susan, Rudbeckia hirta
 
A hero in the pollinator garden. You can't imagine a pollinator garden without it. Black-eyed Susan delights us with its sun-like-looking ray florets throughout the summer. The plant is versatile as it can grow in many conditions, has a moderate height, and looks great with many companion plants.
 
The native species is technically biannual, but since it self-seeds readily, it will persist in good conditions and even fill in some gaps. Black-eyed Susans are sure to make a new planting look good the first year and are a sustainable way to replace annuals with terrible environmental footprints. 
 
Ecology:
Black-eyed Susan supports many species of pollen specialist bees that rely on her to provide their nests with rudbeckia pollen, as their larvae can only feed on rudbeckia pollen. Many tiny flowers bloom in the brown/black cone, providing great nectar and pollen. The yellow petals are just visual guides. Black-eyed Susan is visited by a large variety of pollinators, including butterflies, bee flies, syrphid flies, wasps, ambush bugs and soldier beetles, all beneficial predatory insects to keep your garden in a natural balance.
Many moths and checkerspot butterflies use her leaves as host plants in the caterpillar stage. 
Goldfinches and many other birds feed on the seeds.
 
Growing conditions:
Naturally, black-eyed Susan grows in meadows and prairies in disturbed areas with poor soil. The plant grows best in sunny sites with poor soil.  of average moisture. It can, though, tolerate occasional flooding and drought and part shade. To remain in your garden, black-eyed Susan will have to self-seed, which means some bare ground and good enough growing conditions are needed.