Commonly known as Black-eyed Susans, the varieties I'm offering go above and beyond the classics.  These often come back from seed or overwintering as perennials.  This is a great flower to put in partly shady areas as well.
 
Rudbeckia grows 18-24" tall and gives long slender stems.  Choose the classic Indian Summer for huge blooms and Prairie Sun for that cheery lemon-lime coloring.  Goldilocks offers adorable smaller ruffle blooms in warm golden-honey hues.  
 
Want earthy?  Choose Sahara for soft gold to taupe hues, Cappuccino for two-toned layers, and Cherry Brandy for its jaunty reds.  These will bloom in the summer to give you bright colors on hot days.  Plant 12-18" apart.  While not technically a perennial in our area, they will often reseed and come back.
 
Seedlings are sold in a 2.5" pot.
 
There is no refund or warranty on plants after purchase.