QuestionsHow to growFlowersBorder Perennial Flowerssweet William 0 Vote Up Vote Down Eileen Delany asked 13 years ago When is the best time to take out the sweet william out of the pots to plant in the ground as this is their 2nd year in pots. the pots are outside my house in Sandymount? 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 6 years ago Sweet william is normally grown from seeds sown in summer and planted out in autumn, or direct sown in spring or summer. The plants can be planted at any time from pots but early spring is fine.