[header] How to grow sweet william plants [title] Find out when your sweet william will bloom. [step] Due to the multiple varieties of sweet william and the different methods of growing them, you may hear conflicting information on when your flowers will grow and how long they will last. Biennial varieties bloom in their second year, and then die. 
Perennial varieties are supposed to regrow flowers year after year, but sweet william perennials usually take two years to bloom and often die before they bloom a second time. [substeps] Correct care of sweet william perennials increases the chance of reseeding, as described in the section on caring for sweet william.