Sweet William plants flower in the late spring or early summer and can tolerate cool weather. They grow best is full sun, in quick draining soils. Your average last frost date fall the third or fourth week of May. You can safely plant them in your garden about the second week of May. If you have the plants now and want to plant them in your garden you can, but you'll want to cover them overnight if frost is predicted. Best wishes with your dianthus. |